| Chaperonins assist the proper folding of proteins without being part of the proteins. The eukaryotic cytosolic chaperonin, CCT-Chaperonin Containing TCP-1 (tailess complex polypeptide-1) was the first identified chaperonin from the cytosolic protein and its main substrates are actins and tubulins. So it is involved in the conformation of cytoskeletal proteins and is essential for cell growth. Mammalian CCT is commonly a protein complex composed of 7-9 subunit species. We have isolated a novel full-length cDNA from cDNA library of human test is. This cDNA of 1935 bp contains an 1605 bp open reading frame (ORF) encoding 535 amino acids (aa). We sent the sequence to NCBI (National Center for Biotechnology Information) GenBank database and obtained the GenBank accession number AF026166. The deduced protein of the cDNA is highly homologous to the CCTp subunit of Saccharomyces cerevisiae, Schizosaccharomyces pombe, Caenorhabditis elegans and mouse, etc. Especially high homology (97%) is found between the deduced protein and mouse CCTp. On the basis of such high homology, the protein encoded by the new gene was proposed to be a human CCTP subunit. The human CCTp subunit also contained two highly conserved motifsGDGTTSV(aa96-102) and VY(P/A)GGG (aa408-412), which are ubiqitous in CCT subunits of all organisms. The two conserved peptide regions are related to the hydrolysis of ATP. Northern hybridization showed that human CCTp gene is expressed as a transcript of about 2.0 kb in various tissues. Overexpression was seen in testis with the expression level 3-24 times of that in other tissues. The CCT(3 gene was located on human chromosome 12ql4 by Radiation Hybrid Mapping. Through homologous search, the BAG human with genomic sequence (U91327) was found to be the genomic sequence of 5'-end of CCTp. 7 extrons of 5'-end of CCTp were identified after the comparative analysis of the two sequences.Postgraduate candidate: Jiang juxiang Directed by: professor Jiang yingprofessor Yu long...
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