title: An antagonistic role for the C. elegans Schnurri homolog SMA-9 in modulating TGFbeta signaling during mesodermal patterning.
abstract: In C. elegans, the Sma/Mab TGFbeta signaling pathway regulates body size and male tail patterning. SMA-9, the C. elegans homolog of Schnurri, has been shown to function as a downstream component to mediate the Sma/Mab TGFbeta signaling pathway in these processes. We have discovered a new role for SMA-9 in dorsoventral patterning of the C. elegans post-embryonic mesoderm, the M lineage. In addition to a small body size, sma-9 mutant animals exhibit a dorsal-to-ventral fate transformation within the M lineage. This M lineage defect of sma-9 mutants is unique in that animals carrying mutations in all other known components of the TGFbeta pathway exhibit no M lineage defects. Surprisingly, mutations in the core components of the Sma/Mab TGFbeta signaling pathway suppressed the M lineage defects of sma-9 mutants without suppressing their body size defects. We show that this suppression specifically happens within the M lineage. Our studies have uncovered an unexpected role of SMA-9 in antagonizing the TGFbeta signaling pathway during mesodermal patterning, suggesting a novel mode of function for the SMA-9/Schnurri family of proteins.
authors.affiliation: Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Marisa L
authors.initials: ML
authors.lastname: Foehr
authors.forename: Amanda S
authors.initials: AS
authors.lastname: Lindy
authors.forename: Rachel C
authors.initials: RC
authors.lastname: Fairbank
authors.forename: Nirav M
authors.initials: NM
authors.lastname: Amin
authors.forename: Ming
authors.initials: M
authors.lastname: Xu
authors.forename: Judith
authors.initials: J
authors.lastname: Yanowitz
authors.forename: Andrew Z
authors.initials: AZ
authors.lastname: Fire
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D019521:Body Patterning; D049628:Body Size; D017173:Caenorhabditis elegans / Q000196:embryology* / Q000235:genetics / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000502:physiology*; D004625:Embryo, Nonmammalian / Q000502:physiology*; D017353:Gene Deletion; D008648:Mesoderm / Q000502:physiology*; D015398:Signal Transduction; D014157:Transcription Factors / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D016212:Transforming Growth Factor beta / Q000037:antagonists & inhibitors*; D016335:Zinc Fingers
chemical_list: D029742:Caenorhabditis elegans Proteins; C483687:Sma-9 protein, C elegans; D014157:Transcription Factors; D016212:Transforming Growth Factor beta