Prediction of the coding sequences of unidentified human genes. XX. The complete sequences of 100 new cDNA clones from brain which code for large proteins in vitro

To accumulate information on the coding sequences of unidentified genes, we have carried out a sequencing project of human cDNA clones which encode la rge proteins. We herein present the entire sequences of 100 cDNA clones of unidentified human genes, named KIAA1776 and KIAA1780-KIAA1878, from size-f ractionated cDNA libraries derived from human fetal brain, adult whole brai n? hippocampus and amygdala. Most of the cDNA clones to be entirely sequenc ed were selected as cDNAs which were shown to have coding potentiality by i n vitro transcription/translation experiments, and some clones were chosen by using computer-assisted analysis of terminal sequences of cDNAs. Three o f these clones (fibrillin3/KIAA1776: MEGF10/KIAA1780 and MECF11/KIAA1781) w ere isolated as genes encoding proteins with multiple EGF-like domains by m otif-trap screening. The average sizes of the inserts and corresponding ope n reading frames of cDNA clones analyzed here reached 4.7 kb and 2.4 kb (78 5 amino acid residues), respectively. From the results of homology and moti f searches against the public databases, the functional categories of the p redicted gene products of 54 genes were determined; 93% of these predicted gene products (50 gene products) were classified as proteins related to cel l signaling/communication, nucleic acid management, or cell structure/motil ity. To collect, additional information on these genes, their expression pr ofiles were also studied in 10 human tissues, 8 brain regions, spinal cord, fetal brain and fetal liver by reverse transcription-coupled polymerase ch ain reaction, products of which were quantified by enzyme-linked immunosorb ent assay.