THE MURINE COT PROTOONCOGENE - GENOME STRUCTURE AND TISSUE-SPECIFIC EXPRESSION

We cloned and analyzed the murine cot proto-oncogene and examined its tissue-specific expression in fetal, newborn and adult mice. Genomic c ot DNA consists of eight exons, spanning more than 25 kb, and all intr on-exon borders are well conserved as compared to the human homolog. A nalysis of the full-length cot cDNA revealed that it contained an open reading frame of 1,401 nucleotides, like human cot proto-oncogene. Th e sequence identity between murine and human cot gene is 84.4% at the nucleotide level and 93.9% at the deduced amino acid level. On norther n blot analysis of poly (A)+ RNA, the cot message was detected at 2.9 kb in size. Expression of the cot gene was observed in many tissues fr om fetal to adult mice, though the level of expression was low in all tissues examined.