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Title: Distinct daf-16 isoforms regulate specification of vulval precursor cells in Caenorhabditis elegans
FOXO transcription factors regulate development, longevity, and stress-resistance across species. The C. elegans FOXO ortholog, daf-16, has three major isoforms with distinct promoters and N-termini. Different combinations of isoforms regulate different processes. Adverse environments can induce dauer diapause after the second larval molt. During dauer, daf-16 blocks specification of vulval precursor cells, including EGFR/Ras-mediated 1˚ fate specification and LIN-12/Notch-mediated 2˚ fate specification. Using isoform-specific mutants, we find that daf-16a and daf-16f are functionally redundant for the block to the expression of 1˚ fate markers. In contrast, all three isoforms contribute to blocking the expression of 2˚ fate markers.  more » « less
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microPublication biology
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National Science Foundation
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