Document Actions
Caenorhabditis elegans embryonic axial p ... vered posterior-group Hox genes
Caenorhabditis elegans embryonic axial patterning requires two recently discovered posterior-group Hox genes.
45
Hox genes encode highly conserved transcription factors that control regional identities of cells and tissues along the developing anterior-posterior axis, probably in all bilaterian metazoans. However, in invertebrate embryos other than Drosophila, Hox gene functions remain largely unknown except by inference from sequence similarities and expression patterns. Recent genomic sequencing has shown that Caenorhabditis elegans has three Hox genes of the posterior paralog group [Ruvkun, G. & Hobert, O. (1998) Science 282, 2033-2041]. However, only one has been previously identified genetically, and it is not required for embryonic development [Chisholm, A. (1991) Development (Cambridge, U.K.) 111, 921-932]. Herein, we report identification of the remaining two posterior paralogs as the nob-1 gene and the neighboring php-3 gene. Elimination of nob-1 and php-3 functions causes gross embryonic defects in both posterior patterning and morphogenetic movements of the posterior hypodermis, as well as posterior-to-anterior cell fate transformations and lethality. The only other Hox gene essential for embryogenesis is the labial/Hox1 homolog ceh-13, required for more anterior patterning [Brunschwig, K., Wittmann, C., Schnabel, R., Burglin, T. R., Tobler, H. & Muller, F. (1999) Development (Cambridge, U.K.) 126, 1537-1546]. Therefore, essential embryonic patterning in C. elegans requires only Hox genes of the anterior and posterior paralog groups, raising interesting questions about evolution of the medial-group genes.
Van Auken K, Weaver DC, Edgar LG, Wood WB
Proceedings of the National Academy of Sciences of the United States of America
2000-04-25 00:00
97
9
4499-503
Amino Acid Sequence,Animals,Body Patterning,Caenorhabditis elegans,Caenorhabditis elegans Proteins,Cloning, Molecular,Drosophila,Embryo, Nonmammalian,Genes, Essential,Genes, Homeobox,Molecular Sequence Data,Protein Structure, Secondary,Sequence Alignment,Sequence Homology, Amino Acid,Transcription Factors,Caenorhabditis elegans Proteins,NOB-1 protein, C elegans,PHP-3 protein, C elegans,Transcription Factors
Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309-0347, USA
Proc. Natl. Acad. Sci. U.S.A.
NICHD HD-14958
0027-8424
97/9/4499
1308
True
10781051
