title: Wnt signaling controls temporal identities of seam cells in Caenorhabditis elegans.
abstract: The Wnt signaling pathway regulates multiple aspects of the development of stem cell-like epithelial seam cells in Caenorhabditis elegans, including cell fate specification and symmetric/asymmetric division. In this study, we demonstrate that lit-1, encoding the Nemo-like kinase in the Wnt/beta-catenin asymmetry pathway, plays a role in specifying temporal identities of seam cells. Loss of function of lit-1 suppresses defects in retarded heterochronic mutants and enhances defects in precocious heterochronic mutants. Overexpressing lit-1 causes heterochronic defects opposite to those in lit-1(lf) mutants. LIT-1 exhibits a periodic expression pattern in seam cells within each larval stage. The kinase activity of LIT-1 is essential for its role in the heterochronic pathway. lit-1 specifies the temporal fate of seam cells likely by modulating miRNA-mediated silencing of target heterochronic genes. We further show that loss of function of other components of Wnt signaling, including mom-4, wrm-1, apr-1, and pop-1, also causes heterochronic defects in sensitized genetic backgrounds. Our study reveals a novel function of Wnt signaling in controlling the timing of seam cell development in C. elegans.
authors.affiliation: Graduate Program in Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, PR China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Ren
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism; D019070:Cell Lineage; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004625:Embryo, Nonmammalian / Q000378:metabolism; D020868:Gene Silencing; D006609:High Mobility Group Proteins / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D035683:MicroRNAs / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D043244:Ribonuclease III / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D013234:Stem Cells / Q000166:cytology*; D051153:Wnt Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D029742:Caenorhabditis elegans Proteins; D003598:Cytoskeletal Proteins; D004268:DNA-Binding Proteins; D006609:High Mobility Group Proteins; D008565:Membrane Proteins; D035683:MicroRNAs; C120104:WRM-1 protein, C elegans; D051153:Wnt Proteins; C120084:mom-4 protein, C elegans; C096787:pop-1 protein, C elegans; D017346:Protein Serine-Threonine Kinases; C120085:lit-1 protein, C elegans; C118116:dcr-1 protein, C elegans; D043244:Ribonuclease III