Expression Patterns And Functional Study On Ccd1 Gene

The human Ccdl is a novel gene isolated from the cDNA library of fetal brain. Human Ccdl gene is located on chromosome 11q23. 1, between D11S1391 and D11S1347 loci. The genomic sequence of this gene is 44.58 kb in size. The mRNA of Ccdl, 4803bp in length, is composed of 17 exons. It has a complete coding sequence of 1619 bp, which encodes a protein of 472 amino acids. The protein is only found and highly conserved between the vertebrates. Human Ccdl protein (472 aa) and mouse Ccdl protein (474 aa) showed 90.9% total-amino-acid identity. A tyrosine phosphorylation site (Tyr 242) within the coiled-coil domain was conserved between human and mouse. Leucine zipper motif (codon 202-237) and another tyrosine phosphorylation site (Tyr 272) were identified within the coiled-coil domain of human Ccdl, but not in mouse Ccdl. The bioinformatic analysis of human Ccdl indicated that it possess a coiled-coil domain and Dishevelled-Axin (DIX) domain, which was located at amino acid 120-250 and 390-472, respectively.Recently, Ccdl was identified as a positive regulator in the Wnt signaling pathway during zebrafish neural patterning. Mouse Ccd1, a homologue of zebrafish, was ubiquitously distributed at E9, E10 and E10. 5, but was predominantly expressed in the central nervous system from embryonic day E11.5 to postnatal day P0. These results suggest that Ccdl may play important roles during the development of the nervous system. In order to investigate whether Ccdl functions during the neuronal differentiation, we used the model of neuronal differentiation of P19 cells. We found that the Ccdl overexpressing cells can differentiate into neuronal marker-positive cells in the presence of retinoic acid only for 2 days, which usually need 4 days in wild type cells. The results indicate that overexpression of Ccdl facilitates the neuronal differentiation in P19 cells.The study of the subcellular localization of Ccdl in HEK293 cells was show that the green fluorescence could be seen in cytoplasm in transfected pEGFP-NlCcdl cells and there are some granules assemble near the nucleus. And it was co-localization with centrosome. These results indicate that Ccdl can binding with centrosome and regulate the proliferation, differentiation and apoptosis during the neural development and it possibly functions through the Wnt/JNK singaling pathway.