Cell 1995 Oct 6; 83(1):101-110
The C. elegans gene lin-44, which controls the polarity of certain asymmetric cell divisions, encodes a Wnt protein and acts cell nonautonomously.
Herman, M. A., Vassilieva, L. L., Horvitz, H. R., Shaw, J. E., Herman, R. K.
Department of Genetics and Cell Biology, University of Minnesota, St. Paul 55108, USA.
Mutations in the C. elegans gene lin-44 lead to
reversals in the polarity of certain asymmetric cell divisions. We have
discovered that lin-44 is a member of the Wnt family of genes,
which encode secretory glycoproteins implicated in intercellular
signaling. Both in situ hybridization experiments using lin-44
transcripts and experiments using reporter constructs designed to mimic
patterns of lin-44 expression indicate that lin-44 is
expressed in hypodermal cells at the tip of the tail and posterior to the
cells with polarities affected by lin-44 mutations. Our mosaic
analysis indicates that lin-44 acts cell nonautonomously. We
propose that LIN-44 protein is secreted by tail hypodermal cells and
affects the polarity of asymmetric cell divisions that occur more
anteriorly in the tail.