ALL Metrics
-
Views
-
Downloads
Get PDF
Get XML
Cite
Export
Track
Research Article
Revised

RNAi targeting Caenorhabditis elegans α-arrestins has little effect on lifespan

[version 4; peer review: 3 approved]
Previously titled: RNAi targeting Caenorhabditis elegans α-arrestins has small or no effects on lifespan
PUBLISHED 08 Dec 2017
Author details Author details
OPEN PEER REVIEW
REVIEWER STATUS

Abstract

Background: α-arrestins are a family of proteins that are implicated in multiple biological processes, including metabolism and receptor desensitization.
Methods: Here, we sought to examine the roles of α-arrestins in the longevity of Caenorhabditis elegans through an RNA interference screen.
Results: We found that feeding worms with bacteria expressing double-stranded RNA against each of 24 out of total 29 C. elegans α-arrestins had little effect on lifespan. Thus, individual C. elegans α-arrestins may have minor effects on longevity.
Conclusions: This study will provide useful information for future research on the functional role of α-arrestins in aging and longevity.

Keywords

C. elegans, α-arrestin, insulin/IGF-1 signaling, aging, lifespan

Revised Amendments from Version 3

In response to the reviewers’ comments, we revised our paper and further changes are listed below.
 
1. We changed the “RNAi knock down” to “feeding bacteria expressing dsRNA” to precisely reflect our experimental results.

See the authors' detailed response to the review by Alessandro Bitto
See the authors' detailed response to the review by Roger Pocock
See the authors' detailed response to the review by Meng-Qiu Dong

Introduction

α-arrestins are a family of proteins that contain arrestin domains whose sequences and structures have similarities with those of classical visual and β-arrestins13. α-arrestins are considered as ancestral forms of arrestins because their orthologs exist in fungi, including yeast, which do not have visual or β-arrestins1,4. Several mammalian α-arrestins modulate metabolism and receptor desensitization5,6, but much remains to be elucidated concerning the functions of α-arrestins in many organisms. The human genome encodes 6 α-arrestins and 4 visual or β-arrestins. Interestingly, the simple roundworm Caenorhabditis elegans genome contains 29 α-arrestin and 1 β-arrestin genes1,7. Therefore, the C. elegans system provides opportunities for the genetic analysis of α-arrestins in various aspects of physiology both individually and combinatorially. However, information regarding the functions of C. elegans α-arrestins is limited8,9.

C. elegans is an excellent genetic model organism that has been exploited for studying conserved biological processes, including apoptosis, behavior, development and aging. In particular, its short lifespan in combination with genetic amenability has made C. elegans one of the most popular models for research on aging and longevity10,11. Many factors, including components in insulin/insulin-like growth factor 1 (IGF-1) signaling (IIS), have been identified as lifespan and aging regulators in C. elegans1113. For example, genetic inhibition of IIS components, such as DAF-2/insulin/IGF-1 receptor, robustly extends lifespan and delays physiological aging through up-regulating transcription factors, including DAF-16/FOXO1113. Importantly, the roles of these aging-regulatory factors in C. elegans have been shown to be conserved in other species, including Drosophila and mammals12,13. One of the powerful ways to identify novel factors that influence aging is by employing genetic screens, such as an RNA interference (RNAi) screen. We previously identified several genetic factors, including RNA helicases, that modulate longevity in C. elegans, through targeted or genome-wide RNAi screens1417. Because of its robust longevity phenotype that confers sensitivity to changes in lifespan, daf-2/insulin/IGF-1 receptor mutants serve as an excellent platform for the identification of novel lifespan-regulating factors17,18.

In this study, we aimed to determine whether any α-arrestins played a role in the lifespan regulation of wild-type or daf-2 mutants. We performed a lifespan assay-based RNAi screen targeting 24 out of 29 C. elegans α-arrestins. We found that α-arrestin double-stranded RNA (dsRNA)-expressing E. coli feeding had little effect on the lifespan of wild-type or daf-2 mutants. Thus, C. elegans α-arrestins may play minor or modulatory roles in lifespan regulation. Based on our results, it will be important to test the roles of α-arrestins in combinatorial manners and/or by using strong loss-of-function mutations in future research.

Methods

Caenorhabditis elegans strains

All strains were maintained as previously described19. The following strains were used in this study: N2 wild-type, CF1041 daf-2(e1370) III outcrossed six times to N2.

Phylogenetic analysis

The protein sequences of 27 α-arrestins, except arrd (arrestin domain protein)-20 and arrd-21, were obtained from Wormbase (www.wormbase.org, version WS259). The protein sequences of arrd-20 and arrd-21 were obtained from Ensembl (http://www.ensembl.org, release 89). The phylogenetic tree of 29 α-arrestins in C. elegans was generated using Clustal Omega (http://www.ebi.ac.uk/Tools/msa/clustalo/)20 and re-visualized using the Dendroscope 3 (version 3.5.9)21. For the α-arrestins that have multiple isoforms, isoform a was used for the analysis.

RNAi clones

Twenty one RNAi clones that target C. elegans α-arrestin genes were used from two commercial C. elegans RNAi feeding libraries. Specifically, RNAi clones targeting arrd-2, arrd-6, arrd-7, arrd-8, arrd-9, arrd-10, arrd-13, arrd-16, arrd-18, arrd-23, arrd-24, arrd-25, arrd-28 and ttm-2 (toxin-regulated targets of MAPK 2) were obtained from Ahringer laboratory library (Geneservice Ltd., Cambridge, UK), while those against arrd-1, arrd-3, arrd-4, arrd-5, arrd-14, arrd-15 and arrd-19 were from Vidal laboratory library (Source BioScience, Nottingham, UK). Three RNAi clones targeting arrd-11, arrd-17, and arrd-26 were generated by molecular cloning using infusion recombinase (EZ-FusionTM Cloning Kit, Enzynomics, Daejeon, South Korea). The N2 genomic DNA was obtained through the lysis of worms using proteinase K (Invitrogen, Carlsbad, CA, USA) and N2 complementary DNA was obtained from RNA extraction using RNAiso Plus (Takara, Shiga, Japan) followed by reverse transcription using ImProm-II reverse transcriptase (Promega, Madison, WI, USA, USA). The infusion reaction between PCR products and pL4440 plasmids (Fire lab C. elegans vector kit, 1999) digested with HindIII (New England Biolabs, Ipswich, MA, USA) and Acc65I (New England Biolabs) was followed by transformation of in-house competent E. coli HT115 cells and by selection of positive clones on ampicillin (USB, Santa Clara, CA, USA)-containing LB plates. Primers (CosmoGenetech, Seoul, South Korea) that were used to amplify coding regions of arrd-11 from N2 genomic DNA, and those of arrd-17 and arrd-26 from N2 complementary DNA are as follows: forward primer 5’-GAATTCGATATCAAGCTCCCTCGTGCAAATTAGGAAA-3’ and reverse primer 5’-CTATAGGGCGAATTGGGGTTCCTCCCACTCCATACA-3’ for arrd-11; forward primer 5’-GAATTCGATATCAAGCTATGGTGCAGTTAGATCGTTTTG-3’ and reverse primer 5’-CTATAGGGCGAATTGGTTAATCGGTATAAAATGG-3’ for arrd-17; forward primer 5’-GAATTCGATATCAAGCTATGAAGGTCGATTACTTCG-3’ and reverse primer 5’- CTATAGGGCGAATTGGCTACTTCTCGGAGCCATTTG-3’ for arrd-26. The sequences of all these 24 α-arrestin RNAi clones were confirmed using DNA sequencing (Solgent, Daejeon, South Korea) before lifespan assays. RNAi clone for arrd-12, arrd-22, or arrd-27 was not generated because we were not able to obtain transformed E. coli (HT115) colonies using arrd-12 or arrd-22 infusion reaction products, or the PCR product for arrd-27 genomic or complementary DNA. arrd-20 and arrd-21 are predicted to be pseudogenes (Wormbase, version WS259) and were excluded from our screen. All RNAi clones used in our screen were examined for their potential off-target effects by using Clone Mapper (http://bioinformatics.lif.univ-mrs.fr/RNAiMap)22, and no significant off-target was predicted except arrd-19 RNAi, which may additionally target a predicted pseudogene arrd-21 (Table S1). Experimental validation by qRT-PCR will be necessary to completely exclude the possible off-target effects caused by RNAi clones.

RNAi screen using lifespan assay

The RNAi screen employing lifespan assay was performed as previously described17. Briefly, E. coli HT115 bacteria that expressed specific dsRNAs were cultured overnight at 37°C in LB media containing 50 μg/ml ampicillin (USB). The cultured bacteria were seeded onto nematode growth media plates containing 50 μg/ml ampicillin and incubated overnight at 37°C. The seeded bacteria were treated with 1 mM isopropyl β-D-1-thiogalactopyranoside (Gold Biotechnology, St. Louis, MO, USA) and incubated at room temperature for approximately 24 h to induce dsRNAs. Age-synchronized wild-type N2 and daf-2(e1370) mutant animals were grown on RNAi plates from embryo to L4 stage at 20°C. Worms were then transferred onto RNAi plates containing 5 μM 5-fluoro-2’deoxyuridine (FUdR; Sigma, St. Louis, MO, USA), which prevents eggs from hatching, at young (day 1) adult stage, and transferred again to new FUdR-containing RNAi plates after 1 or 2 days. Eggs laid by ttm-2 RNAi-treated worms hatched more frequently than control eggs on FUdR-containing plates in two independent lifespan experiments. All lifespan assays were performed at 20°C as duplicates by two independent researchers. The survival of worms was determined by gently touching worms with a platinum wire. Worms that did not respond were counted as dead worms and removed from the plates. Worms that crawled off the plates, burrowed into the agar media, or displayed internal hatching or vulval rupture were censored, but included in the statistical analysis. Lifespan data from two independent lifespan experiments within the experimental sets were pooled and used for statistical analysis (see Dataset 1Dataset 3). OASIS 2 (Online Application for Survival Analysis 2; https://sbi.postech.ac.kr/oasis2)23 was used for the statistical analysis of lifespan results. P values were calculated using long-rank (Mantel-Cox method) test.

Results

Feeding bacteria expressing dsRNA against each of several C. elegans α-arrestins marginally influenced lifespan

We measured the lifespan of wild-type and long-lived daf-2 mutant animals fed with bacteria expressing dsRNA targeting each of 24 of 29 genes encoding putative α-arrestin proteins (Figure 1A). We used daf-16 RNAi that largely suppressed the longevity of daf-2(-) mutants as a positive control (Figure 1B, Figure S1A, Table S2)17,18. We found that feeding bacteria expressing dsRNA against specific α-arrestin genes caused a minor reduction of lifespan in wild-type or in daf-2(-) mutants (Figure 1B, Figure S1B–U, Table S2). Out of the 24 RNAi clones, bacteria expressing dsRNA targeting arrd (arrestin domain protein)-13, arrd-16, arrd-23, arrd-24 or arrd-25 in wild-type, and bacteria expressing dsRNA against arrd-1, arrd-2, arrd-5, arrd-24 or arrd-28 in daf-2(-) mutant animals decreased lifespan by more than 5% (Figure 1B–E, Figures S1B, D, K, Q, R, T, Table S2). Specifically, bacteria expressing dsRNA against arrd-16 decreased lifespan in wild-type by 9%, and bacteria expressing dsRNA against arrd-1 decreased lifespan in daf-2(-) mutants by 7% (Figure 1B and C). In addition, bacteria expressing dsRNA targeting arrd-24 decreased the lifespan of wild-type and daf-2 mutant animals by 11% and 6%, respectively (Figure 1E). In contrast, bacteria expressing dsRNA against arrd-3 increased the lifespan of wild-type animals by 10% (Figure 1F). Overall, feeding C. elegans with bacteria expressing dsRNA against individual α-arrestin genes appears to have minor effects on lifespan.

e4a8ff6a-2a4f-4759-a8da-85c56f34c340_figure1.gif

Figure 1. Feeding bacteria expressing dsRNA targeting each of Caenorhabditis elegans α-arrestins had little effect on lifespan.

(A) A phylogenetic tree showing C. elegans α-arrestin family members. Asterisks (*) indicate α-arrestins that were not examined in this study and number signs (#) indicate predicted pseudogenes. (B) Each circle represents percent mean lifespan change by feeding wild-type (WT) and daf-2(e1370) (daf-2(-)) mutants with bacteria expressing dsRNA against each of α-arrestin genes. Red triangles indicate lifespan changes by daf-16 RNAi bacteria feeding, which was used as a positive control. (CF) Lifespan curves of WT and daf-2(-) animals fed with dsRNA-expressing bacteria targeting arrd-16 (C), arrd-1 (D), arrd- 24 (E), and arrd-3 (F). See Table S2 for statistical analysis.

SetStrainTreatmentDaysAt RiskDeadCensoredPercent MortalityS_hatVar S_hatSE(S)Survival TimePercent Alive
1N2Control RNAi02400001000100
1N2Control RNAi12400001000100
1N2Control RNAi22400001000100
1N2Control RNAi42401150.420.99600.0040.01799.6
1N2Control RNAi5224020.420.99600.0040.01799.6
1N2Control RNAi62222191.310.98700.0080.0798.7
1N2Control RNAi7201011.310.98700.0080.0798.7
1N2Control RNAi82002102.30.97700.010.14997.7
1N2Control RNAi10188625.420.94600.0160.46194.6
1N2Control RNAi1118031070.9300.0180.63593
1N2Control RNAi1216710112.560.8740.0010.0241.30387.4
1N2Control RNAi1415644437.230.6280.0010.0364.75662.8
1N2Control RNAi1610828253.50.4650.0010.0387.3646.5
1N2Control RNAi187821166.020.340.0010.0369.61334
1N2Control RNAi205614174.510.2550.0010.03311.31225.5
1N2Control RNAi22415077.620.2240.0010.03211.99622.4
1N2Control RNAi233617088.190.1180.0010.02514.42611.8
1N2Control RNAi24195091.30.08700.02215.1728.7
1N2Control RNAi25147095.650.04400.01616.264.4
1N2Control RNAi2673097.510.02500.01216.7452.5
1N2Control RNAi2844010000017.4410
1N2daf-16 RNAi02400001000100
1N2daf-16 RNAi12400001000100
1N2daf-16 RNAi22400001000100
1N2daf-16 RNAi42402280.830.99200.0060.03399.2
1N2daf-16 RNAi5210020.830.99200.0060.03399.2
1N2daf-16 RNAi62081201.310.98700.0080.06298.7
1N2daf-16 RNAi7187051.310.98700.0080.06298.7
1N2daf-16 RNAi8182473.480.96500.0130.23596.5
1N2daf-16 RNAi10171918.560.91400.0210.74391.4
1N2daf-16 RNAi1116137929.570.7040.0010.0343.05570.4
1N2daf-16 RNAi1211510235.70.6430.0010.0363.7964.3
1N2daf-16 RNAi1410348565.660.3430.0010.0377.98534.3
1N2daf-16 RNAi165025382.830.1720.0010.03110.73217.2
1N2daf-16 RNAi182212092.20.0780.0010.02312.4187.8
1N2daf-16 RNAi20107097.660.02300.01313.512.3
1N2daf-16 RNAi2233010000014.0250
1N2arrd-1 RNAi02400001000100
1N2arrd-1 RNAi12400001000100
1N2arrd-1 RNAi22400001000100
1N2arrd-1 RNAi424001201000100
1N2arrd-1 RNAi52280301000100
1N2arrd-1 RNAi62251380.440.99600.0040.02799.6
1N2arrd-1 RNAi7186010.440.99600.0040.02799.6
1N2arrd-1 RNAi81850120.440.99600.0040.02799.6
1N2arrd-1 RNAi10173201.60.98400.0090.14298.4
1N2arrd-1 RNAi1117117711.380.8860.0010.0241.21888.6
1N2arrd-1 RNAi121475214.390.8560.0010.0271.5885.6
1N2arrd-1 RNAi1414036336.410.6360.0010.0374.66163.6
1N2arrd-1 RNAi1610125152.150.4790.0020.0397.1847.9
1N2arrd-1 RNAi187526268.740.3130.0010.03710.16631.3
1N2arrd-1 RNAi204710175.390.2460.0010.03411.49624.6
1N2arrd-1 RNAi223610082.220.1780.0010.03113.00117.8
1N2arrd-1 RNAi232614091.80.0820.0010.02215.2028.2
1N2arrd-1 RNAi24126095.90.04100.01616.1864.1
1N2arrd-1 RNAi2561096.580.03400.01516.3573.4
1N2arrd-1 RNAi2654099.320.00700.00717.0680.7
1N2arrd-1 RNAi2811010000017.260
1N2arrd-2 RNAi02400001000100
1N2arrd-2 RNAi12400001000100
1N2arrd-2 RNAi22400001000100
1N2arrd-2 RNAi424001301000100
1N2arrd-2 RNAi52270001000100
1N2arrd-2 RNAi62271300.440.99600.0040.02699.6
1N2arrd-2 RNAi7196000.440.99600.0040.02699.6
1N2arrd-2 RNAi81960180.440.99600.0040.02699.6
1N2arrd-2 RNAi10178332.120.97900.0110.19497.9
1N2arrd-2 RNAi1117216211.220.8880.0010.0241.19688.8
1N2arrd-2 RNAi121544013.530.8650.0010.0261.47386.5
1N2arrd-2 RNAi1415036334.280.6570.0010.0364.37865.7
1N2arrd-2 RNAi1611122047.310.5270.0010.0386.46252.7
1N2arrd-2 RNAi188928063.880.3610.0010.0379.44636.1
1N2arrd-2 RNAi206120075.730.2430.0010.03311.81424.3
1N2arrd-2 RNAi22417079.870.2010.0010.03112.72620.1
1N2arrd-2 RNAi233421092.30.07700.0215.5857.7
1N2arrd-2 RNAi24135095.260.04700.01616.2964.7
1N2arrd-2 RNAi2582096.450.03600.01416.5923.6
1N2arrd-2 RNAi2664098.820.01200.00817.2081.2
1N2arrd-2 RNAi2822010000017.5390
1N2arrd-3 RNAi02400001000100
1N2arrd-3 RNAi12400001000100
1N2arrd-3 RNAi22400001000100
1N2arrd-3 RNAi42400601000100
1N2arrd-3 RNAi52340101000100
1N2arrd-3 RNAi62332230.860.99100.0060.05299.1
1N2arrd-3 RNAi7208000.860.99100.0060.05299.1
1N2arrd-3 RNAi82082131.810.98200.0090.12898.2
1N2arrd-3 RNAi10193212.830.97200.0110.2397.2
1N2arrd-3 RNAi11190706.410.93600.0170.62393.6
1N2arrd-3 RNAi12183418.450.91500.020.86991.5
1N2arrd-3 RNAi1417827822.340.7770.0010.032.81377.7
1N2arrd-3 RNAi1614320333.20.6680.0010.0344.55166.8
1N2arrd-3 RNAi1812025147.120.5290.0010.0377.05652.9
1N2arrd-3 RNAi209418057.240.4280.0010.0379.08142.8
1N2arrd-3 RNAi227618067.370.3260.0010.03511.30932.6
1N2arrd-3 RNAi235832185.370.1460.0010.02615.44914.6
1N2arrd-3 RNAi242510091.220.08800.02116.8538.8
1N2arrd-3 RNAi25155094.150.05900.01817.5855.9
1N2arrd-3 RNAi26104096.490.03500.01418.1933.5
1N2arrd-3 RNAi2865099.410.00600.00619.0120.6
1N2arrd-3 RNAi3011010000019.1880
1N2arrd-4 RNAi02400001000100
1N2arrd-4 RNAi12400001000100
1N2arrd-4 RNAi22400001000100
1N2arrd-4 RNAi424001501000100
1N2arrd-4 RNAi52250201000100
1N2arrd-4 RNAi62231220.450.99600.0040.02799.6
1N2arrd-4 RNAi7200000.450.99600.0040.02799.6
1N2arrd-4 RNAi82002151.440.98600.0080.10798.6
1N2arrd-4 RNAi10183453.60.96400.0130.32296.4
1N2arrd-4 RNAi1117420314.680.8530.0010.0261.54185.3
1N2arrd-4 RNAi121516218.070.8190.0010.0291.94881.9
1N2arrd-4 RNAi1414324431.820.6820.0010.0353.87368.2
1N2arrd-4 RNAi1611517341.90.5810.0010.0375.48558.1
1N2arrd-4 RNAi189517152.30.4770.0010.0387.35747.7
1N2arrd-4 RNAi207721065.310.3470.0010.0379.95934.7
1N2arrd-4 RNAi225611072.120.2790.0010.03511.45827.9
1N2arrd-4 RNAi234522085.750.1420.0010.02714.59314.2
1N2arrd-4 RNAi24235088.850.1120.0010.02515.33611.2
1N2arrd-4 RNAi25184091.330.08700.02215.9568.7
1N2arrd-4 RNAi26145094.420.05600.01816.7615.6
1N2arrd-4 RNAi2898099.380.00600.00618.1490.6
1N2arrd-4 RNAi3011010000018.3350
1N2arrd-5 RNAi02400001000100
1N2arrd-5 RNAi12400001000100
1N2arrd-5 RNAi22400001000100
1N2arrd-5 RNAi42400901000100
1N2arrd-5 RNAi52310301000100
1N2arrd-5 RNAi62285272.190.97800.010.13297.8
1N2arrd-5 RNAi7196112.690.97300.0110.16797.3
1N2arrd-5 RNAi81940152.690.97300.0110.16797.3
1N2arrd-5 RNAi10179334.320.95700.0140.3395.7
1N2arrd-5 RNAi11173979.30.90700.0210.87790.7
1N2arrd-5 RNAi121572010.460.89500.0221.01689.5
1N2arrd-5 RNAi1415541634.140.6590.0010.0364.33265.9
1N2arrd-5 RNAi1610819245.730.5430.0010.0386.18654.3
1N2arrd-5 RNAi188725161.320.3870.0010.0388.99338.7
1N2arrd-5 RNAi206130280.340.1970.0010.03112.79719.7
1N2arrd-5 RNAi22299086.440.1360.0010.02714.13913.6
1N2arrd-5 RNAi232011193.90.06100.01915.8546.1
1N2arrd-5 RNAi2482095.430.04600.01716.224.6
1N2arrd-5 RNAi2564098.480.01500.01116.9821.5
1N2arrd-5 RNAi2621099.240.00800.00817.1810.8
1N2arrd-5 RNAi2811010000017.3940
1daf-2(e1370)Control RNAi02100001000100
1daf-2(e1370)Control RNAi12100001000100
1daf-2(e1370)Control RNAi22100001000100
1daf-2(e1370)Control RNAi42100601000100
1daf-2(e1370)Control RNAi72040801000100
1daf-2(e1370)Control RNAi81960001000100
1daf-2(e1370)Control RNAi101960401000100
1daf-2(e1370)Control RNAi111920301000100
1daf-2(e1370)Control RNAi131890401000100
1daf-2(e1370)Control RNAi14185130.540.99500.0050.07699.5
1daf-2(e1370)Control RNAi16181211.640.98400.0090.25298.4
1daf-2(e1370)Control RNAi18178001.640.98400.0090.25298.4
1daf-2(e1370)Control RNAi19178102.190.97800.0110.35797.8
1daf-2(e1370)Control RNAi20177062.190.97800.0110.35797.8
1daf-2(e1370)Control RNAi22171102.760.97200.0120.48297.2
1daf-2(e1370)Control RNAi23170022.760.97200.0120.48297.2
1daf-2(e1370)Control RNAi251682173.920.96100.0150.77296.1
1daf-2(e1370)Control RNAi28149426.50.93500.0191.49493.5
1daf-2(e1370)Control RNAi30143026.50.93500.0191.49493.5
1daf-2(e1370)Control RNAi311417011.140.8890.0010.0252.93388.9
1daf-2(e1370)Control RNAi331341011.810.8820.0010.0263.15288.2
1daf-2(e1370)Control RNAi341336115.780.8420.0010.0294.50484.2
1daf-2(e1370)Control RNAi361262117.120.8290.0010.034.98682.9
1daf-2(e1370)Control RNAi371237121.840.7820.0010.0336.73178.2
1daf-2(e1370)Control RNAi381154124.560.7540.0010.0357.76475.4
1daf-2(e1370)Control RNAi4011010031.420.6860.0010.03810.50768.6
1daf-2(e1370)Control RNAi411003033.470.6650.0010.03811.35166.5
1daf-2(e1370)Control RNAi439712041.70.5830.0020.0414.8958.3
1daf-2(e1370)Control RNAi44856145.820.5420.0020.04116.70154.2
1daf-2(e1370)Control RNAi467823061.790.3820.0020.0424.0538.2
1daf-2(e1370)Control RNAi495526079.860.2010.0010.03332.920.1
1daf-2(e1370)Control RNAi512910086.80.1320.0010.02836.44213.2
1daf-2(e1370)Control RNAi52196090.970.090.0010.02438.619
1daf-2(e1370)Control RNAi54135094.440.05600.01940.4855.6
1daf-2(e1370)Control RNAi5583096.530.03500.01541.6313.5
1daf-2(e1370)Control RNAi5752097.920.02100.01242.4232.1
1daf-2(e1370)Control RNAi6032099.310.00700.00743.2570.7
1daf-2(e1370)Control RNAi6311010000043.6940
1daf-2(e1370)daf-16 RNAi02400001000100
1daf-2(e1370)daf-16 RNAi12400001000100
1daf-2(e1370)daf-16 RNAi22400001000100
1daf-2(e1370)daf-16 RNAi42400301000100
1daf-2(e1370)daf-16 RNAi72374121.690.98300.0080.11898.3
1daf-2(e1370)daf-16 RNAi8221011.690.98300.0080.11898.3
1daf-2(e1370)daf-16 RNAi10220423.480.96500.0120.29796.5
1daf-2(e1370)daf-16 RNAi11214415.280.94700.0150.49594.7
1daf-2(e1370)daf-16 RNAi13209226.190.93800.0160.61393.8
1daf-2(e1370)daf-16 RNAi14205829.850.90200.021.12690.2
1daf-2(e1370)daf-16 RNAi1619511114.930.8510.0010.0241.93985.1
1daf-2(e1370)daf-16 RNAi1818310019.580.8040.0010.0272.77680.4
1daf-2(e1370)daf-16 RNAi1917316027.020.730.0010.034.18973
1daf-2(e1370)daf-16 RNAi2015718335.390.6460.0010.0325.86364.6
1daf-2(e1370)daf-16 RNAi2213617143.460.5650.0010.0347.6456.5
1daf-2(e1370)daf-16 RNAi2311833059.270.4070.0010.03411.27640.7
1daf-2(e1370)daf-16 RNAi258530073.650.2640.0010.0314.8726.4
This is a portion of the data; to view all the data, please download the file.
Dataset 1.Kaplan-Meier estimator of RNAi lifespan experiments.
Kaplan-Meier estimate values were calculated from pooled lifespan data of two independent lifespan experiments using OASIS2 (https://sbi.postech.ac.kr/oasis2/). ‘At risk’ indicates the number of individuals at risk just prior to a specific time point. ‘S_hat’ indicates Kaplan-Meier estimate of survival function, ‘Var S_hat’ indicates variance of ‘S_hat’, and ‘SE(S)’ indicates standard error of ‘S_hat’.
SetStrainTreatmentNumber of subjectsMean survival daysStandard error of mean survival95 percent confidence interval of meanAge in days at 25 percent mortailtyAge in days at 50 percent mortailtyAge in days at 75 percent mortailtyAge in days at 90 percent mortailtyAge in days at 100 percent mortailty95 percent median confidence interval25 percent linear interpolation of mortality curve50 percent linear interpolation of mortality curve75 percent linear interpolation of mortality curve90 percent linear interpolation of mortality curve100 percent linear interpolation of mortality curve
1N2control RNAi24017.440.3516.75 ~ 18.13141622242816.0 ~ 16.013.0115.5720.3123.5828
1N2daf-16 RNAi24014.030.2513.54 ~ 14.511114161822- ~ -10.7812.9515.0917.5322
1N2arrd-1 RNAi24017.260.3416.60 ~ 17.92141620232816.0 ~ 16.012.9615.7319.8822.8128
1N2arrd-2 RNAi24017.540.3316.89 ~ 18.19141820232816.0 ~ 16.013.1116.3219.8822.8128
1N2arrd-3 RNAi24019.190.3418.53 ~ 19.85162023243018.0 ~ 18.014.4918.5722.4223.7930
1N2arrd-4 RNAi24018.340.3917.56 ~ 19.11141823253018.0 ~ 18.013.0117.5622.2124.4630
1N2arrd-5 RNAi24017.390.3216.76 ~ 18.02141820232816.0 ~ 16.013.2316.5519.4422.4828
1daf-2(e1370)control RNAi21043.690.6942.35 ~ 45.04404649526344.0 ~ 44.038.1344.5248.1951.7763
1daf-2(e1370)daf-16 RNAi24022.520.3721.79 ~ 23.25192328283422.0 ~ 22.018.7322.4125.2227.6334
1daf-2(e1370)arrd-1 RNAi18040.810.8539.15 ~ 42.47364346526041.0 ~ 44.034.7642.4945.8851.3460
1daf-2(e1370)arrd-2 RNAi21041.470.6640.18 ~ 42.76364446515743.0 ~ 43.035.7543.1745.950.1557
1daf-2(e1370)arrd-3 RNAi24043.320.6542.04 ~ 44.59384649526343.0 ~ 44.037.4244.0348.5251.7763
1daf-2(e1370)arrd-4 RNAi24041.740.6540.45 ~ 43.02374349526041.0 ~ 43.036.3442.3647.0951.5560
1daf-2(e1370)arrd-5 RNAi24041.110.639.93 ~ 42.28374346515741.0 ~ 43.036.0841.4945.8150.2657
2N2control RNAi24021.660.3520.97 ~ 22.36182224273421.0 ~ 21.017.012123.9426.5134
2N2daf-16 RNAi24017.630.3117.02 ~ 18.24151822242718.0 ~ 18.012.5116.8921.0922.5127
2N2arrd-6 RNAi24020.510.4319.68 ~ 21.35151924303719.0 ~ 21.014.2718.9823.9327.1537
2N2arrd-7 RNAi24020.920.3920.17 ~ 21.68152124273419.0 ~ 21.014.7719.823.8126.8534
2N2arrd-8 RNAi24020.520.4219.69 ~ 21.35152124303019.0 ~ 21.013.9419.3123.7727.7230
2N2arrd-9 RNAi24020.770.3920.00 ~ 21.54152124273419.0 ~ 19.014.7119.2723.8526.9134
2N2arrd-10 RNAi24020.220.4119.42 ~ 21.02152124273019.0 ~ 21.013.7919.623.4626.5330
2daf-2(e1370)control RNAi24044.310.7342.88 ~ 45.75394851576244.0 ~ 45.037.7845.2950.3755.1862
2daf-2(e1370)daf-16 RNAi24125.280.4124.47 ~ 26.09212430344024.0 ~ 24.020.623.5827.8533.0940
2daf-2(e1370)arrd-6 RNAi24044.250.6642.95 ~ 45.54394551556244.0 ~ 45.038.2944.7949.2554.5162
2daf-2(e1370)arrd-7 RNAi24043.090.7441.64 ~ 44.55374551556244.0 ~ 45.036.1544.5249.5454.8462
2daf-2(e1370)arrd-8 RNAi24043.330.6642.04 ~ 44.61394548546244.0 ~ 45.038.944.0647.9952.1862
2daf-2(e1370)arrd-9 RNAi24043.590.6642.30 ~ 44.88404551546244.0 ~ 45.039.4144.6848.4352.9262
2daf-2(e1370)arrd-10 RNAi24046.020.7544.56 ~ 47.48404855596645.0 ~ 45.039.4546.2354.1857.4466
3N2control RNAi24019.830.3219.21 ~ 20.451720242434- ~ -16.3519.2522.4223.9834
3N2daf-16 RNAi24014.820.2214.40 ~ 15.25121417182214.0 ~ 14.011.5313.9216.7117.9822
3N2arrd-13 RNAi21018.670.318.08 ~ 19.27161822243018.0 ~ 18.015.3817.9620.2423.2930
3N2arrd-14 RNAi24019.130.318.53 ~ 19.72162022242818.0 ~ 18.015.9318.5821.5323.7328
3N2arrd-15 RNAi24018.860.3218.23 ~ 19.49142022263018.0 ~ 18.013.7618.2420.8324.9530
3N2arrd-16 RNAi24017.980.3117.38 ~ 18.58141720242817.0 ~ 17.013.3616.8919.8123.9228
3N2arrd-18 RNAi24018.890.3318.25 ~ 19.54141822263217.0 ~ 18.013.8917.9421.1425.0532
3daf-2(e1370)control RNAi21044.890.8543.23 ~ 46.55384753587144.0 ~ 47.037.8645.3952.8557.1371
3daf-2(e1370)daf-16 RNAi24023.450.3322.80 ~ 24.11202426283824.0 ~ 24.018.9423.225.6727.8338
3daf-2(e1370)arrd-13 RNAi21045.690.943.92 ~ 47.46404753597044.0 ~ 47.038.0546.0752.3557.4370
3daf-2(e1370)arrd-14 RNAi24042.940.8441.30 ~ 44.58374450566744.0 ~ 44.036.0943.5149.9454.367
3daf-2(e1370)arrd-15 RNAi24045.790.6744.47 ~ 47.114147515667- ~ -40.1545.4450.7355.5367
3daf-2(e1370)arrd-16 RNAi24043.290.8241.68 ~ 44.89374751566444.0 ~ 44.036.6544.8250.4954.2364
3daf-2(e1370)arrd-18 RNAi18045.10.9543.24 ~ 46.96384753596444.0 ~ 47.037.6345.4452.2658.5464
4N2control RNAi24018.040.2817.49 ~ 18.59151821232917.0 ~ 18.014.1317.4320.2822.4529
4N2daf-16 RNAi24014.850.2114.44 ~ 15.26121517182314.0 ~ 14.011.7314.2416.3817.9823
4N2arrd-23 RNAi24016.780.316.19 ~ 17.38141719232715.0 ~ 17.013.0316.1518.9921.8127
4N2arrd-24 RNAi24016.050.2215.61 ~ 16.49141518212615.0 ~ 15.012.8214.9117.1619.8526
4N2arrd-25 RNAi24016.860.2716.32 ~ 17.391517192126- ~ -12.9415.9418.5620.7426
4N2arrd-26 RNAi24017.220.2816.66 ~ 17.78151719232915.0 ~ 15.012.8615.3718.8422.729
4N2arrd-28 RNAi24017.530.2717.00 ~ 18.07151721232917.0 ~ 17.013.416.7919.3121.9229
4daf-2(e1370)control RNAi21045.930.7544.45 ~ 47.40395053566149.0 ~ 49.038.8849.0352.6855.1561
4daf-2(e1370)daf-16 RNAi24020.290.3519.60 ~ 20.97182124272918.0 ~ 18.015.3218.7523.4326.729
4daf-2(e1370)arrd-23 RNAi24044.150.742.78 ~ 45.51374752566046.0 ~ 47.036.846.7151.1553.4460
4daf-2(e1370)arrd-24 RNAi211430.7541.52 ~ 44.47394650535946.0 ~ 46.038.2944.8249.3652.8159
4daf-2(e1370)arrd-25 RNAi24043.740.6442.47 ~ 45.00404650535946.0 ~ 46.039.5345.9749.4752.4159
4daf-2(e1370)arrd-26 RNAi24144.670.6443.42 ~ 45.93394752535946.0 ~ 47.038.3946.6150.3252.9459
4daf-2(e1370)arrd-28 RNAi15043.520.8541.85 ~ 45.19374750535646.0 ~ 47.036.8646.1349.6552.5356
5N2control RNAi24020.310.4319.47 ~ 21.16152124283819.0 ~ 19.01519.7623.8627.238
5N2daf-16 RNAi24015.630.3514.95 ~ 16.31121518222714.0 ~ 15.010.8714.4517.8821.6627
5N2arrd-11 RNAi24020.170.4219.35 ~ 20.99172125274019.0 ~ 19.015.2919.6524.0526.3940
5N2arrd-17 RNAi24020.520.4119.72 ~ 21.33172124274019.0 ~ 19.016.2219.6523.1626.5140
5N2arrd-19 RNAi24019.560.4118.75 ~ 20.36151924273618.0 ~ 19.014.618.723.2325.936
5N2ttm-2 RNAi24019.110.4418.24 ~ 19.97151924273618.0 ~ 19.014.2818.0722.3926.6236
5daf-2(e1370)control RNAi24042.970.741.60 ~ 44.33384650546142.0 ~ 42.036.5542.7449.3853.1261
5daf-2(e1370)daf-16 RNAi24321.540.3720.82 ~ 22.27172125283821.0 ~ 21.016.8820.7324.227.6238
5daf-2(e1370)arrd-11 RNAi21042.180.7240.77 ~ 43.59384250545842.0 ~ 42.035.8741.7849.2252.5358
5daf-2(e1370)arrd-17 RNAi24041.320.6240.09 ~ 42.543842465459- ~ -35.5740.0745.4652.1659
5daf-2(e1370)arrd-19 RNAi24041.10.5939.94 ~ 42.263842465059- ~ -35.7240.7244.6849.6259
Dataset 2.Mean lifespan and mortality rates of RNAi experiment results.
Mean lifespan, ages at different percent mortality, linear interpolation of mortality curve at specific mortality rate were calculated from pooled lifespan data of two independent lifespan experiments. Data were obtained using OASIS2 (https://sbi.postech.ac.kr/oasis2/).
SetCondition 1 strainCondition 1 treatmentCondition 2 strainCondition 2 treatmentChi squareP valueBonferroni P value
1N2control RNAiN2daf-16 RNAi60.0400
1N2control RNAiN2arrd-1 RNAi0.690.40681
1N2control RNAiN2arrd-2 RNAi0.080.77991
1N2control RNAiN2arrd-3 RNAi8.090.00450.0268
1N2control RNAiN2arrd-4 RNAi3.070.07980.4786
1N2control RNAiN2arrd-5 RNAi0.470.49411
1daf-2(e1370)control RNAidaf-2(e1370)daf-16 RNAi342.2300
1daf-2(e1370)control RNAidaf-2(e1370)arrd-1 RNAi4.870.02740.1642
1daf-2(e1370)control RNAidaf-2(e1370)arrd-2 RNAi6.390.01150.0344
1daf-2(e1370)control RNAidaf-2(e1370)arrd-3 RNAi00.96331
1daf-2(e1370)control RNAidaf-2(e1370)arrd-4 RNAi2.540.11070.6644
1daf-2(e1370)control RNAidaf-2(e1370)arrd-5 RNAi9.050.00260.0157
2N2control RNAiN2daf-16 RNAi60.5500
2N2control RNAiN2arrd-6 RNAi1.410.23561
2N2control RNAiN2arrd-7 RNAi0.710.39931
2N2control RNAiN2arrd-8 RNAi0.940.33241
2N2control RNAiN2arrd-9 RNAi1.230.26751
2N2control RNAiN2arrd-10 RNAi3.240.0720.432
2daf-2(e1370)control RNAidaf-2(e1370)daf-16 RNAi311.9700
2daf-2(e1370)control RNAidaf-2(e1370)arrd-6 RNAi0.570.45141
2daf-2(e1370)control RNAidaf-2(e1370)arrd-7 RNAi0.590.4431
2daf-2(e1370)control RNAidaf-2(e1370)arrd-8 RNAi3.790.05160.3099
2daf-2(e1370)control RNAidaf-2(e1370)arrd-9 RNAi3.220.07290.4376
2daf-2(e1370)control RNAidaf-2(e1370)arrd-10 RNAi5.820.01580.0948
3N2control RNAiN2daf-16 RNAi158.4300
3N2control RNAiN2arrd-138.810.0030.018
3N2control RNAiN2arrd-143.810.05090.3053
3N2control RNAiN2arrd-1530.08310.4983
3N2control RNAiN2arrd-1615.50.00010.0005
3N2control RNAiN2arrd-182.20.13810.8287
3daf-2(e1370)control RNAidaf-2(e1370)daf-16 RNAi309.0800
3daf-2(e1370)control RNAidaf-2(e1370)arrd-130.540.46071
3daf-2(e1370)control RNAidaf-2(e1370)arrd-144.090.04330.2596
3daf-2(e1370)control RNAidaf-2(e1370)arrd-150.020.88751
3daf-2(e1370)control RNAidaf-2(e1370)arrd-162.450.11740.7042
3daf-2(e1370)control RNAidaf-2(e1370)arrd-180.490.4861
4N2control RNAiN2daf-16 RNAi85.1400
4N2control RNAiN2arrd-23 RNAi7.030.0080.0481
4N2control RNAiN2arrd-24 RNAi33.810.0000000060.000000036
4N2control RNAiN2arrd-25 RNAi9.40.00220.013
4N2control RNAiN2arrd-26 RNAi2.240.13420.8053
4N2control RNAiN2arrd-28 RNAi1.510.21881
4daf-2(e1370)control RNAidaf-2(e1370)daf-16 RNAi392.7600
4daf-2(e1370)control RNAidaf-2(e1370)arrd-23 RNAi8.340.00390.0233
4daf-2(e1370)control RNAidaf-2(e1370)arrd-24 RNAi20.60.00000560.000034
4daf-2(e1370)control RNAidaf-2(e1370)arrd-25 RNAi24.90.000000610.0000036
4daf-2(e1370)control RNAidaf-2(e1370)arrd-26 RNAi11.750.00060.0037
4daf-2(e1370)control RNAidaf-2(e1370)arrd-28 RNAi17.710.0000260.0002
5N2control RNAiN2daf-16 RNAi67.4700
5N2control RNAiN2arrd-11 RNAi0.080.77071
5N2control RNAiN2arrd-17 RNAi00.99141
5N2control RNAiN2arrd-19 RNAi1.720.18910.9455
5N2control RNAiN2ttm-2 RNAi3.220.07290.3644
5daf-2(e1370)control RNAidaf-2(e1370)daf-16 RNAi368.100
5daf-2(e1370)control RNAidaf-2(e1370)arrd-11 RNAi1.010.31561
5daf-2(e1370)control RNAidaf-2(e1370)arrd-17 RNAi5.850.01560.078
5daf-2(e1370)control RNAidaf-2(e1370)arrd-19 RNAi11.490.00070.0035
Dataset 3.Statistical analysis of lifespan data.
Statistical test results (Chi square, p value, Bonferroni p value) were calculated between ‘condition 1’ and ‘condition 2’. Test results were obtained using OASIS2 (https://sbi.postech.ac.kr/oasis2/).

Discussion

The lifespan-regulatory functions of α-arrestins remain largely unexplored at the organism level. Here we showed that feeding bacteria expressing dsRNA targeting individual C. elegans α-arrestins had little effect on lifespan in wild-type or daf-2 mutants. Our study has limitations that need to be considered for interpretation. First, feeding RNAi targeting some α-arrestins might be insufficient for causing strong lifespan phenotypes. This may be because many of C. elegans α-arrestins are predicted to be expressed in neurons7,9,2426, which are refractory to RNAi2729. Lifespan assays using RNAi-hypersensitive mutants, including rrf-3(-) and eri-1(-) animals2931, treated with α-arrestin RNAi, or using α-arrestin null mutants will help address this issue. In addition, as we did not test whether RNAi targeting each α-arrestin gene was effective by using quantitative RT-PCR, our negative data should be interpreted with caution. Second, C. elegans α-arrestins may have functional redundancy, considering the large number of the α-arrestin family members in C. elegans and their sequence similarity1,7, which may obscure examining the functional importance of each α-arrestin. In addition, some α-arrestins may mostly function by modulating the action of their interacting proteins6. In this case, genetic inhibition of α-arrestins may rather subtly affect the functions of their interacting partners that directly regulate physiology, such as aging and longevity, causing weak or no phenotypes. Thus, it will be interesting to test the effects of simultaneous inhibition of α-arrestins possibly through targeting the arrestin domain, and to identify and to functionally characterize proteins that bind C. elegans α-arrestins. Third, it is possible that three α-arrestins, arrd-12, arrd-22 and arrd-27, which were not tested in our screen, may play crucial roles in lifespan regulation. Thus, it will be important to examine if genetic inhibition of each of these three α-arrestin genes affects lifespan in future studies.

In mammals, several α-arrestins are implicated in metabolic regulation5. TXNIP (thioredoxin-interacting protein), an inhibitor of thioredoxin in mammals3234, is a crucial negative regulator of glucose uptake35,36. ARRDC4 inhibits glucose uptake in cultured mammalian cells as well36, and ARRDC3 deficiency protects against obesity in male mice through increasing energy expenditure37. Because metabolism is closely associated with aging38, it will be interesting to test whether α-arrestins in complex metazoans play roles in aging via regulating metabolism.

Data availability

Dataset 1. Kaplan-Meier estimator of RNAi lifespan experiments. Kaplan-Meier estimate values were calculated from pooled lifespan data of two independent lifespan experiments using OASIS2 (https://sbi.postech.ac.kr/oasis2/). ‘At risk’ indicates the number of individuals at risk just prior to a specific time point. ‘S_hat’ indicates Kaplan-Meier estimate of survival function, ‘Var S_hat’ indicates variance of ‘S_hat’, and ‘SE(S)’ indicates standard error of ‘S_hat’. doi, 10.5256/f1000research.12337.d17315839

Dataset 2. Mean lifespan and mortality rates of RNAi experiment results. Mean lifespan, ages at different percent mortality, linear interpolation of mortality curve at specific mortality rate were calculated from pooled lifespan data of two independent lifespan experiments. Data were obtained using OASIS2 (https://sbi.postech.ac.kr/oasis2/). doi, 10.5256/f1000research.12337.d17315940

Dataset 3. Statistical analysis of lifespan data. Statistical test results (Chi square, p value, Bonferroni p value) were calculated between ‘condition 1’ and ‘condition 2’. Test results were obtained using OASIS2 (https://sbi.postech.ac.kr/oasis2/). doi, 10.5256/f1000research.12337.d17316041

Comments on this article Comments (0)

Version 4
VERSION 4 PUBLISHED 18 Aug 2017
Comment
Author details Author details
Competing interests
Grant information
Copyright
Download
 
Export To
metrics
Views Downloads
F1000Research - -
PubMed Central
Data from PMC are received and updated monthly.
- -
Citations
CITE
how to cite this article
Park S, Jung Y, An SWA et al. RNAi targeting Caenorhabditis elegans α-arrestins has little effect on lifespan [version 4; peer review: 3 approved]. F1000Research 2017, 6:1515 (https://doi.org/10.12688/f1000research.12337.4)
NOTE: If applicable, it is important to ensure the information in square brackets after the title is included in all citations of this article.
track
receive updates on this article
Track an article to receive email alerts on any updates to this article.

Open Peer Review

Current Reviewer Status: ?
Key to Reviewer Statuses VIEW
ApprovedThe paper is scientifically sound in its current form and only minor, if any, improvements are suggested
Approved with reservations A number of small changes, sometimes more significant revisions are required to address specific details and improve the papers academic merit.
Not approvedFundamental flaws in the paper seriously undermine the findings and conclusions
Version 4
VERSION 4
PUBLISHED 08 Dec 2017
Revised
Views
7
Cite
Reviewer Report 15 Dec 2017
Alessandro Bitto, Department of Pathology, University of Washington, Seattle, Seattle, WA, USA 
Approved
VIEWS 7
No ... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Bitto A. Reviewer Report For: RNAi targeting Caenorhabditis elegans α-arrestins has little effect on lifespan [version 4; peer review: 3 approved]. F1000Research 2017, 6:1515 (https://doi.org/10.5256/f1000research.14574.r28842)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
Version 3
VERSION 3
PUBLISHED 14 Nov 2017
Revised
Views
15
Cite
Reviewer Report 15 Nov 2017
Alessandro Bitto, Department of Pathology, University of Washington, Seattle, Seattle, WA, USA 
Approved with Reservations
VIEWS 15
I appreciate the wish for the authors to move past this set of experiments and communicate their results to the field. Nevertheless, I must reiterate that, without testing the efficacy of their RNAi, their results cannot be interpreted, rather than be ... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Bitto A. Reviewer Report For: RNAi targeting Caenorhabditis elegans α-arrestins has little effect on lifespan [version 4; peer review: 3 approved]. F1000Research 2017, 6:1515 (https://doi.org/10.5256/f1000research.14215.r27946)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
  • Author Response (F1000Research Advisory Board Member) 08 Dec 2017
    Seung-Jae V Lee, Korea Advanced Institute of Science and Technology, South Korea
    08 Dec 2017
    Author Response F1000Research Advisory Board Member
    Dear Dr. Alessandro Bitto,

    We greatly appreciate your time and efforts for further valuable comments. We totally agree with your concern that we do not know the degree of RNAi knockdown ... Continue reading
COMMENTS ON THIS REPORT
  • Author Response (F1000Research Advisory Board Member) 08 Dec 2017
    Seung-Jae V Lee, Korea Advanced Institute of Science and Technology, South Korea
    08 Dec 2017
    Author Response F1000Research Advisory Board Member
    Dear Dr. Alessandro Bitto,

    We greatly appreciate your time and efforts for further valuable comments. We totally agree with your concern that we do not know the degree of RNAi knockdown ... Continue reading
Version 2
VERSION 2
PUBLISHED 19 Oct 2017
Revised
Views
19
Cite
Reviewer Report 26 Oct 2017
Alessandro Bitto, Department of Pathology, University of Washington, Seattle, Seattle, WA, USA 
Approved with Reservations
VIEWS 19
The authors took effort to address most of the concerns we raised in our initial review, but did not address at all our major concern, apart from a note in the discussion about the limitations of their results.

... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Bitto A. Reviewer Report For: RNAi targeting Caenorhabditis elegans α-arrestins has little effect on lifespan [version 4; peer review: 3 approved]. F1000Research 2017, 6:1515 (https://doi.org/10.5256/f1000research.13946.r27143)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
  • Author Response (F1000Research Advisory Board Member) 14 Nov 2017
    Seung-Jae V Lee, Korea Advanced Institute of Science and Technology, South Korea
    14 Nov 2017
    Author Response F1000Research Advisory Board Member
    Dear Dr. Alessandro Bitto,
    We greatly appreciate your comments and respect your concerns on our paper. We totally agree with your point that providing evidence for RNAi targeting arrd genes is ... Continue reading
COMMENTS ON THIS REPORT
  • Author Response (F1000Research Advisory Board Member) 14 Nov 2017
    Seung-Jae V Lee, Korea Advanced Institute of Science and Technology, South Korea
    14 Nov 2017
    Author Response F1000Research Advisory Board Member
    Dear Dr. Alessandro Bitto,
    We greatly appreciate your comments and respect your concerns on our paper. We totally agree with your point that providing evidence for RNAi targeting arrd genes is ... Continue reading
Views
14
Cite
Reviewer Report 24 Oct 2017
Meng-Qiu Dong, National Institute of Biological Sciences (NCBS), Beijing, China 
Approved
VIEWS 14
In this paper, Park et al. knocked down 24 out of 29 alpha-arrestin genes in C. elegans and found that none of them produced a sizable effect on the lifespans of the wild type or the long-lived daf-2 worms. The ... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Dong MQ. Reviewer Report For: RNAi targeting Caenorhabditis elegans α-arrestins has little effect on lifespan [version 4; peer review: 3 approved]. F1000Research 2017, 6:1515 (https://doi.org/10.5256/f1000research.13946.r25721)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
  • Author Response (F1000Research Advisory Board Member) 14 Nov 2017
    Seung-Jae V Lee, Korea Advanced Institute of Science and Technology, South Korea
    14 Nov 2017
    Author Response F1000Research Advisory Board Member
    Dear Dr. Meng-Qiu Dong,
    We sincerely thank you for your valuable comments on our manuscript. We admit the limitations of our research and revised our manuscript to downplay our results so ... Continue reading
COMMENTS ON THIS REPORT
  • Author Response (F1000Research Advisory Board Member) 14 Nov 2017
    Seung-Jae V Lee, Korea Advanced Institute of Science and Technology, South Korea
    14 Nov 2017
    Author Response F1000Research Advisory Board Member
    Dear Dr. Meng-Qiu Dong,
    We sincerely thank you for your valuable comments on our manuscript. We admit the limitations of our research and revised our manuscript to downplay our results so ... Continue reading
Views
11
Cite
Reviewer Report 20 Oct 2017
Roger Pocock, Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Department of Anatomy and Developmental Biology, Monash University, Melbourne, Vic, Australia 
Approved
VIEWS 11
The authors have partially addressed my concerns. Below I suggest further changes.
  1. Change title from 'RNAi targeting Caenorhabditis elegans α-arrestins has small or no effects on lifespan' to 'RNAi targeting Caenorhabditis elegans α-arrestins has little effect on lifespan'
... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Pocock R. Reviewer Report For: RNAi targeting Caenorhabditis elegans α-arrestins has little effect on lifespan [version 4; peer review: 3 approved]. F1000Research 2017, 6:1515 (https://doi.org/10.5256/f1000research.13946.r27142)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
  • Author Response (F1000Research Advisory Board Member) 14 Nov 2017
    Seung-Jae V Lee, Korea Advanced Institute of Science and Technology, South Korea
    14 Nov 2017
    Author Response F1000Research Advisory Board Member
    Dear Dr. Roger Pocock,
    We greatly appreciate your comments on our manuscript. We further addressed your concerns and revised our manuscript as described below.
     
    The authors have partially addressed my concerns. Below ... Continue reading
COMMENTS ON THIS REPORT
  • Author Response (F1000Research Advisory Board Member) 14 Nov 2017
    Seung-Jae V Lee, Korea Advanced Institute of Science and Technology, South Korea
    14 Nov 2017
    Author Response F1000Research Advisory Board Member
    Dear Dr. Roger Pocock,
    We greatly appreciate your comments on our manuscript. We further addressed your concerns and revised our manuscript as described below.
     
    The authors have partially addressed my concerns. Below ... Continue reading
Version 1
VERSION 1
PUBLISHED 18 Aug 2017
Views
22
Cite
Reviewer Report 06 Sep 2017
Roger Pocock, Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Department of Anatomy and Developmental Biology, Monash University, Melbourne, Vic, Australia 
Approved with Reservations
VIEWS 22
In this manuscript Park et al. performed RNAi knockdown of 24 of the 29 alpha-arrestin genes in C. elegans to ask whether they are important for lifespan regulation in wild type and daf-2 mutant animals. Their data shows that, in ... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Pocock R. Reviewer Report For: RNAi targeting Caenorhabditis elegans α-arrestins has little effect on lifespan [version 4; peer review: 3 approved]. F1000Research 2017, 6:1515 (https://doi.org/10.5256/f1000research.13357.r25722)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
  • Author Response (F1000Research Advisory Board Member) 14 Nov 2017
    Seung-Jae V Lee, Korea Advanced Institute of Science and Technology, South Korea
    14 Nov 2017
    Author Response F1000Research Advisory Board Member
    Dear Dr. Roger Pocock,
    We sincerely appreciate your valuable comments on our manuscript. We agree with all your points and revised our manuscript to describe the limitations of this study. ... Continue reading
COMMENTS ON THIS REPORT
  • Author Response (F1000Research Advisory Board Member) 14 Nov 2017
    Seung-Jae V Lee, Korea Advanced Institute of Science and Technology, South Korea
    14 Nov 2017
    Author Response F1000Research Advisory Board Member
    Dear Dr. Roger Pocock,
    We sincerely appreciate your valuable comments on our manuscript. We agree with all your points and revised our manuscript to describe the limitations of this study. ... Continue reading
Views
30
Cite
Reviewer Report 04 Sep 2017
Alessandro Bitto, Department of Pathology, University of Washington, Seattle, Seattle, WA, USA 
Jason Pitt, Department of Pathology, University of Washington, Seattle, WA, USA 
Approved with Reservations
VIEWS 30
In the manuscript RNAi targeting Caenorhabditis elegans alpha-arrestins marginally affects lifespan Park and co-workers provide largely negative results from lifespan experiments following RNAi knockdown of most of the worm alpha-arrestins.  While we welcome the effort to publish negative results, there is ... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Bitto A and Pitt J. Reviewer Report For: RNAi targeting Caenorhabditis elegans α-arrestins has little effect on lifespan [version 4; peer review: 3 approved]. F1000Research 2017, 6:1515 (https://doi.org/10.5256/f1000research.13357.r25290)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
  • Author Response (F1000Research Advisory Board Member) 14 Nov 2017
    Seung-Jae V Lee, Korea Advanced Institute of Science and Technology, South Korea
    14 Nov 2017
    Author Response F1000Research Advisory Board Member
    Dear Dr. Alessandro Bitto and Dr. Jason Pitt,
    We greatly appreciate the reviewers’ valuable comments on our manuscript. We agree with all the reviewers’ comments and modified our manuscript to ... Continue reading
COMMENTS ON THIS REPORT
  • Author Response (F1000Research Advisory Board Member) 14 Nov 2017
    Seung-Jae V Lee, Korea Advanced Institute of Science and Technology, South Korea
    14 Nov 2017
    Author Response F1000Research Advisory Board Member
    Dear Dr. Alessandro Bitto and Dr. Jason Pitt,
    We greatly appreciate the reviewers’ valuable comments on our manuscript. We agree with all the reviewers’ comments and modified our manuscript to ... Continue reading

Comments on this article Comments (0)

Version 4
VERSION 4 PUBLISHED 18 Aug 2017
Comment
Alongside their report, reviewers assign a status to the article:
Approved - the paper is scientifically sound in its current form and only minor, if any, improvements are suggested
Approved with reservations - A number of small changes, sometimes more significant revisions are required to address specific details and improve the papers academic merit.
Not approved - fundamental flaws in the paper seriously undermine the findings and conclusions
Sign In
If you've forgotten your password, please enter your email address below and we'll send you instructions on how to reset your password.

The email address should be the one you originally registered with F1000.

Email address not valid, please try again

You registered with F1000 via Google, so we cannot reset your password.

To sign in, please click here.

If you still need help with your Google account password, please click here.

You registered with F1000 via Facebook, so we cannot reset your password.

To sign in, please click here.

If you still need help with your Facebook account password, please click here.

Code not correct, please try again
Email us for further assistance.
Server error, please try again.