The lin-11 LIM domain transcription factor is necessary for morphogenesis of C-elegans uterine cells

The Caenorhabditis elegans hermaphrodite egg-laying system comprises severa l tissues, including the uterus and vulva. lin-11 encodes a LIM domain tran scription factor needed for certain vulval precursor cells to divide asymme trically. Based on lin-11 expression studies and the lin-11 mutant phenotyp e, we find that lin-11 is also required for C. elegans uterine morphogenesi s, Specifically, lin-11 is expressed in the ventral uterine intermediate pr ecursor pi cells and their progeny (the utse and uv1 cells), which connect the uterus to the vulva. Like pi cell induction, the uterine lin-11 express ion responds to the uterine anchor cell and the lin-12-encoded receptor. In wild type animals, the utse, which forms the planar process at the uterine -vulval interface, fuses with the anchor cell. We found that, in lin-11 mut ants, utse differentiation was abnormal, the utse failed to fuse with the a nchor cell and a functional uterine-vulval connection was not made. These f indings indicate that lin-11 is essential for uterine-vulval morphogenesis.