Human Gene Creb4 And 4.10 Cloning And Functional Studies

From our large cDNA cloning and sequencing plan, by cDNA microarray analysis together with bioinformatics analysis, we selected 2 genes as follows for further research.Extracellular stimuli elicit changes in gene expression in target cells by activating intracellular protein kinase cascades thay phosphorylate transcription factor within the nucleus. Cyclic AMP responsive element binding protein (CREB) is perhaps the best characterized stimulus-induced transcription factor. We report here the cloning and characterization of a novel human CREB gene(CREB4). The gene encoded a protein of 395 amino acids residues, which shared high homology to mouse CREB3. The expression pattern of human CREB4 gene showed that there is a transcript in pancreas, prostate , brain, skeletal muscle, small intestine kidney, leukocyte, testis, thymus and, colon adenocarcinoma CX-1,colon carcinoma GI-112, LX-1,prastatic adenocarcinoma PC-3, pancreatic adenocarcinoma GI-103, whereas in lung, liver, colon, placenta, heart, spleen, ovary, and lung carcinoma GI-117,breast carcinoma, ovarian carcinoma, specific bands of the transcript could not be detected. An over-expression has been observed in colon adenocarcinoma CX-1. The human CREB4 gene was located to human chromosome between 1q21.3 by bioinformatics analysis. cDNA microarray analysis revealed its expression level is move up in liver cancer. GFP location of CREB4 gene product shows the full length of the protein located in the cytoplasm and while the C-teminal-cleaved mutant in the cell nucleus. We have done yeast-two-hybrid analysis of CREB4 to identify other proteins with which it interacts. We identified 2 protein,karyopherin and TPR, interacted with CREB4. Protein 4.1 is a basic component of the membrane skeleton mainly with spctrin in the erythrocytes, and playing the vital role in remaining the congfigure and mechanical capability. We identified a novel human 4.1 gene that was 2312bp of length and encoded a protein of 553 amino acids residues(4.1O).. The expression pattern of human 4.1O gene showed that there is a transcript in Ovary, fetal brain and fetal thrymus whereas in heart, brain, spleen, testis, ovary, small intestine and leukocyte specific bands of the transcript could not be detected. An over-expression has been observed in colon adenocarcinoma CX-1. 4.1O gene consists of nine exons and eight introns and is mapped to14q11.1-14q11.2 in chromosome. cDNA microarray analysis indicated its expression level is move up in liver cancer and stomach cancer.