[Transcription-active locus of the human genome from a gene family]

Previously described genomic sequences, related to viral oncogene mos (human mos pseudogene gp5 and main c-mos gene), are either totally silent or show highly limited degree of expression in some specialized tissues. The mos-related clone K51 isolated previously from rat genome was used here to study expression of the gene comprised. We have demonstrated the presence of abundant transcripts in rat and human brain, lung, skin and muscle. The pattern of transcription changes after the birth and is shown to depend on the presence of higher molecular weight transcripts in adult tissues. With the help of hybridization to K51 probe, we have isolated three clones from human embryonic cDNA library. One of these (son3) also hybridizes to the viral mos gene. These results evidence strongly in favour of the hypothesis that K51 recombinant contains a new member (son) of mos-related family of oncogenes, with the broad spectrum of tissue specificity.