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This content will become publicly available on January 21, 2026

Title: SEM-2/SoxC regulates multiple aspects of C. elegans postembryonic mesoderm development
Development of multicellular organisms requires well-orchestrated interplay between cell-intrinsic transcription factors and cell-cell signaling. One set of highly conserved transcription factors that plays diverse roles in development is the SoxC group.C.eleganscontains a sole SoxC protein, SEM-2. SEM-2 is essential for embryonic development, and for specifying the sex myoblast (SM) fate in the postembryonic mesoderm, the M lineage. We have identified a novel partial loss-of-functionsem-2allele that has a proline to serine change in the C-terminal tail of the highly conserved DNA-binding domain. Detailed analyses of mutant animals harboring this point mutation uncovered new functions of SEM-2 in the M lineage. First, SEM-2 functions antagonistically with LET-381, the soleC.elegansFoxF/C forkhead transcription factor, to regulate dorsoventral patterning of the M lineage. Second, in addition to specifying the SM fate, SEM-2 is essential for the proliferation and diversification of the SM lineage. Finally, SEM-2 appears to directly regulate the expression ofhlh-8, which encodes a basic helix-loop-helix Twist transcription factor and plays critical roles in proper patterning of the M lineage. Our data, along with previous studies, suggest an evolutionarily conserved relationship between SoxC and Twist proteins. Furthermore, our work identified new interactions in the gene regulatory network (GRN) underlyingC.eleganspostembryonic development and adds to the general understanding of the structure-function relationship of SoxC proteins.  more » « less
Award ID(s):
2349577 1950247
PAR ID:
10568475
Author(s) / Creator(s):
; ; ; ; ;
Editor(s):
Grant, Barth D
Publisher / Repository:
PLoS Genetics
Date Published:
Journal Name:
PLOS Genetics
Volume:
21
Issue:
1
ISSN:
1553-7404
Page Range / eLocation ID:
e1011361
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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