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Abstract ARGONAUTES are the central effector proteins ofRNAsilencing which bind target transcripts in a smallRNA‐guided manner.Arabidopsis thalianahas 10ARGONAUTE(AGO) genes, with specialized roles inRNA‐directedDNAmethylation, post‐transcriptional gene silencing, and antiviral defense. To better understand specialization amongAGOgenes at the level of transcriptional regulation we tested a library of 1497 transcription factors for binding to the promoters ofAGO1,AGO10, andAGO7using yeast 1‐hybrid assays. A ranked list of candidateDNA‐bindingTFs revealed binding of theAGO7promoter by a number of proteins in two families: the miR156‐regulatedSPLfamily and the miR319‐regulatedTCPfamily, both of which have roles in developmental timing and leaf morphology. Possible functions forSPLandTCPbinding are unclear: we showed that these binding sites are not required for the polar expression pattern ofAGO7, nor for the function ofAGO7in leaf shape. NormalAGO7transcription levels and function appear to depend instead on an adjacent 124‐bp region. Progress in understanding the structure of this promoter may aid efforts to understand how the conservedAGO7‐triggeredTAS3pathway functions in timing and polarity.
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Egg viability decreases rapidly with time since ovulation in the rainbow darter Etheostoma caeruleum : implications for the costs of choosiness
Egg viability in the rainbow darterEtheostoma caeruleum, a fish apparently lacking female mate choice, was found to decline rapidly after ovulation. It was observed that the majority of a female's clutch may fail to hatch if she is prevented from mating for as little as 6 h. These data suggest that exercising female mate preferences may be selectively disfavoured inE. caeruleumdue to the high cost of delaying mating.
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- Award ID(s):
- 1701676
- PAR ID:
- 10048028
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Fish Biology
- Volume:
- 92
- Issue:
- 2
- ISSN:
- 0022-1112
- Page Range / eLocation ID:
- p. 532-536
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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