PROSITE documentation PDOC51496

CVC domain profile

Homeobox-containing genes encode transcription factors and are characterized by the homeodomain (HD) (see <PDOC00027>), a motif that directs specific DNA binding to regulate the expression of target genes. Homeobox genes are grouped into several subclasses according to the primary structure of their HD and its flanking sequences. Among the paired-like subclass, the paired-like CVC (PLC)-homeodomain proteins (HDPs) are characterized by a conserved CVC domain and can be grouped into the Vsx-1 and Vsx-2 family, containing orthologs from several species. The characteristic feature of the Vsx-1 group are the existence of a RV domain and LG sequence and the lack of a Paired-Tail/OAR domain (see <PDOC50803>). Instead of an RV domain, the Vsx-2 group proteins have a conserved 14 amino acid motif called the Paired-Tail or OAR domain. These specific domain differences may correlate with the functional specificity of each group. PLC-HDPs appear to play a particular role in occular development and execute their functions by binding to the conserved locus control region (LCR), located upstream of the transcrption initiation site of the red opsin gene, and thus specify the development and differenciation of cone photoreceptors and a subset of retinal inner nuclear layer bipolar cells. The CVC (standing for Chx10/Vsx-1 and ceh-10) domain consists of approximately 50-60 amino acid residues. Because the CVC domain is located immediately C-terminal to the homeodomain, the CVC domain is predicted to influence transcriptional regulation through DNA-binding, protein-protein interaction and/or protein degradation processes. It is possible that the CVC domain is necessary for protein folding or protein-protein interactions because this domain is hydrophobic [1,2,3].

The profile we developed covers the entire CVC domain.