Cloning and characterization of CIS 1b (cytokine inducible SH2-containing protein 1b), an alternative splicing form of CIS 1 gene

JAK-STAT pathway is essential in relaying cytokine signals and plays a vita l role in cellular responses such as proliferation, differentiation and imm unity. Some members of a recently found citokine-inducible SH2 protein (CIS , =SOCS or SSI) family have proved to have negative effects on modulating J AK-STAT signaling pathway. In the present study, a novel human cDNA (CIS1b) which proved to be a variant of CIS1 gene was isolated by screen human pla centa lambda gt11 cDNA library and 5'-rapid amplification of cDNA ends (RAC E). Furthermore, the gene structure of CIS1 was determined by comparing the cDNA sequences of CIS1 and CIS1b to the genomic sequence in human chromoso me 3p21.3. The expression patterns of CIS1b as well as CIS1 were analysed b y Northern blot.