Abstract
The Drosophila argonaute2 (ago2) gene plays a major role in siRNA mediated RNA silencing pathways. Unlike mammalian Argonaute proteins, the Drosophila protein has an unusual amino-terminal domain made up largely of multiple copies of glutamine-rich repeats (GRRs). We report here that the ago2 locus produces an alternative transcript that encodes a putative short isoform without this amino-terminal domain. Several ago2 mutations previously reported to be null alleles only abolish expression of the long, GRR-containing isoform. Analysis of drop out (dop) mutations had previously suggested that variations in GRR copy number result in defects in RNAi and embryonic development. However, we find that dop mutations genetically complement transcript-null alleles of ago2 and that ago2 alleles with variant GRR copy numbers support normal development. In addition, we show that the assembly of the central RNAi machinery, the RISC (RNA induced silencing complex), is unimpaired in embryos when GRR copy number is altered. In fact, we find that GRR copy number is highly variable in natural D. melanogaster populations as well as in laboratory strains. Finally, while many other insects share an extensive, glutamine-rich Ago2 amino-terminal domain, its primary sequence varies drastically between species. Our data indicate that GRR variation does not modulate an essential function of Ago2 and that the amino-terminal domain of Ago2 is subject to rapid evolution.
| Original language | English |
|---|---|
| Article number | e15264 |
| Pages (from-to) | 1-14 |
| Number of pages | 14 |
| Journal | PLoS One |
| Volume | 5 |
| Issue number | 12 |
| DOIs | |
| Publication status | Published - 2010 |
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ASJC Scopus subject areas
- Agricultural and Biological Sciences(all)
- Biochemistry, Genetics and Molecular Biology(all)
- Medicine(all)
Cite this
Natural Variation of the Amino-Terminal Glutamine-Rich Domain in Drosophila Argonaute2 Is Not Associated with Developmental Defects. / Hain, Daniel; Bettencourt, Brian R.; Okamura, Katsutomo; Csorba, Tibor; Meyer, Wibke; Jin, Zhigang; Biggerstaff, Jason; Siomi, Haruhiko; Hutvagner, Gyorgy; Lai, Eric C.; Welte, Michael; Müller, H. Arno J.
In: PLoS One, Vol. 5, No. 12, e15264, 2010, p. 1-14.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Natural Variation of the Amino-Terminal Glutamine-Rich Domain in Drosophila Argonaute2 Is Not Associated with Developmental Defects
AU - Hain, Daniel
AU - Bettencourt, Brian R.
AU - Okamura, Katsutomo
AU - Csorba, Tibor
AU - Meyer, Wibke
AU - Jin, Zhigang
AU - Biggerstaff, Jason
AU - Siomi, Haruhiko
AU - Hutvagner, Gyorgy
AU - Lai, Eric C.
AU - Welte, Michael
AU - Müller, H. Arno J
PY - 2010
Y1 - 2010
N2 - The Drosophila argonaute2 (ago2) gene plays a major role in siRNA mediated RNA silencing pathways. Unlike mammalian Argonaute proteins, the Drosophila protein has an unusual amino-terminal domain made up largely of multiple copies of glutamine-rich repeats (GRRs). We report here that the ago2 locus produces an alternative transcript that encodes a putative short isoform without this amino-terminal domain. Several ago2 mutations previously reported to be null alleles only abolish expression of the long, GRR-containing isoform. Analysis of drop out (dop) mutations had previously suggested that variations in GRR copy number result in defects in RNAi and embryonic development. However, we find that dop mutations genetically complement transcript-null alleles of ago2 and that ago2 alleles with variant GRR copy numbers support normal development. In addition, we show that the assembly of the central RNAi machinery, the RISC (RNA induced silencing complex), is unimpaired in embryos when GRR copy number is altered. In fact, we find that GRR copy number is highly variable in natural D. melanogaster populations as well as in laboratory strains. Finally, while many other insects share an extensive, glutamine-rich Ago2 amino-terminal domain, its primary sequence varies drastically between species. Our data indicate that GRR variation does not modulate an essential function of Ago2 and that the amino-terminal domain of Ago2 is subject to rapid evolution.
AB - The Drosophila argonaute2 (ago2) gene plays a major role in siRNA mediated RNA silencing pathways. Unlike mammalian Argonaute proteins, the Drosophila protein has an unusual amino-terminal domain made up largely of multiple copies of glutamine-rich repeats (GRRs). We report here that the ago2 locus produces an alternative transcript that encodes a putative short isoform without this amino-terminal domain. Several ago2 mutations previously reported to be null alleles only abolish expression of the long, GRR-containing isoform. Analysis of drop out (dop) mutations had previously suggested that variations in GRR copy number result in defects in RNAi and embryonic development. However, we find that dop mutations genetically complement transcript-null alleles of ago2 and that ago2 alleles with variant GRR copy numbers support normal development. In addition, we show that the assembly of the central RNAi machinery, the RISC (RNA induced silencing complex), is unimpaired in embryos when GRR copy number is altered. In fact, we find that GRR copy number is highly variable in natural D. melanogaster populations as well as in laboratory strains. Finally, while many other insects share an extensive, glutamine-rich Ago2 amino-terminal domain, its primary sequence varies drastically between species. Our data indicate that GRR variation does not modulate an essential function of Ago2 and that the amino-terminal domain of Ago2 is subject to rapid evolution.
UR - http://www.scopus.com/inward/record.url?scp=78650724121&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=78650724121&partnerID=8YFLogxK
U2 - 10.1371/journal.pone.0015264
DO - 10.1371/journal.pone.0015264
M3 - Article
C2 - 21253006
AN - SCOPUS:78650724121
VL - 5
SP - 1
EP - 14
JO - PLoS One
JF - PLoS One
SN - 1932-6203
IS - 12
M1 - e15264
ER -