ISOLATION OF CDNA CLONE ENCODING HUMAN HOMOLOG OF SENESCENCE MARKER PROTEIN-30 (SMP30) AND ITS LOCATION ON THE X-CHROMOSOME

We have isolated and characterized a cDNA clone encoding human homolog ue of senescence marker protein-30 (SMP30), a calcium binding protein also called regucalcin (RC). This clone (pHSMP6) has 1356 base pairs ( bp) and contains an open reading frame of 897 bp, which encodes 299 am ino acids. The estimated molecular weight of the deduced polypeptide i s 33 250 and pI is 5.836. The homology of amino acid sequences between human homologue and rat SMP30 is 88.6%. Using pHSMP6 as a probe, the chromosomal location of the human homologue of SMP30 gene was determin ed, The results of regional mapping using a panel of 11 rodent-human s omatic hybrids indicated that the gene is located in the p11.3-q11.2 s egment of the X chromosome. This gene thus could be a candidate for on e of the X-linked diseases mapped to this regions,