[Cloning and structural analysis of 5'-flanking sequence of human hepatic stimulator substance (hHSS) gene].

Human hepatic stimulator substance (hHSS) is a newly identified growth-promoting factor in liver. HSS is capable of stimulating the hepatic regeneration in hepaectomized rats and promoting the growth of hepatic tumor cells. To understand and elucidate the regulation of hHSS on hepatocyte growth at genetic level, the 4,890 bp of 5'-flanking region of hHSS gene have been isolated and sequenced. On basis of comparison of the 5'-flanking sequences with GenBank, hHSS gene was localized on human chromosome 16. Transcriptional start site was identified by reverse transcriptase-polymerase chain reaction (RT-PCR) and 5' rapid amplification of cDNA end (5'RACE). The initiation nucleotide was defined as 'C', which located at 254 bp upstream of the reported sequence of exon I.