RT Journal
A1 Popovici, Cornel
A1 Roubin, Régine
A1 Coulier, François
A1 Pontarotti, Pierre
A1 Birnbaum, Daniel
T1 The Family of Caenorhabditis elegans Tyrosine Kinase Receptors: Similarities and Differences with Mammalian Receptors
JF Genome Research 
JO Genome Research 
YR 1999 
FD November 01 
VO 9 
IS 11 
SP 1026 
OP 1039 
DO 10.1101/gr.9.11.1026 
UL http://genome.cshlp.org/content/9/11/1026.abstract 
AB Transmembrane receptors with tyrosine kinase activity (RTK) constitute a superfamily of proteins present in all metazoans that is associated with the control and regulation of cellular processes. They have been the focus of numerous studies and are a good subject for comparative analyses of multigene families in different species aimed at understanding metazoan evolution. The sequence of the genome of the nematode worm Caenorhabditis elegans is available. This offers a good opportunity to study the superfamily of nematode RTKs in its entirety and to compare it with its mammalian counterpart. We show that the C. elegans RTKs constitute various groups with different phylogenetic relationships with mammalian RTKs. A group of four RTKs show structural similarity with the three mammalian receptors for the vascular endothelial growth factors. Another group comprises RTKs with a short extracellular region, a feature not known in mammals; the genes encoding these RTKs are clustered on chromosome II with other gene families, including genes encoding chitinase-like proteins. Most of theC. elegans RTKs have no direct orthologous relationship with any mammalian RTK, providing an illustration of the importance of the separate evolution of the different phyla.[The sequences in this paper have been submitted to GenBank under the following accession numbers: AF188748, AF188749, AF188750, and AF188751.]