The CG-1 gene, a member of the kinectin and ES/130 family, maps to human chromosome band 14q22.

Abstract

CG-1 is a member of a novel gene family of coiled-coil proteins that includes the chicken proteins kinectin and ES/ 130 (C. G. Print and G. W. Krissansen, manuscript submitted). Full-length CG-1 cDNA clones isolated from a human leukocyte library encode a 1300 amino acid residue polypeptide distinguished by the presence of multiple contiguous coiled-coil heptad-containing segments in the Cterminal 1000 amino acids (Print et al. 1994). CG-1 mRNA transcripts are detectable in diverse human tissues including testes, ovary, spleen, thymus, prostate, and small intestine (Print et al. 1994), and a CG-l-specific antiserum immunoprecipitates a disulfide-linked dimer of 150 000 Mr polypeptides from the surface of radioiodinated peripheral blood mononuclear cells (Print and Krissansen, 1995). The related ES/130 molecule is an extracellular matrix protein involved in heart development (Rezaee et al. 1993; Print and Krissansen, 1995), and kinectin appears to be a major kinesin-binding protein located at the cytoplasmic face of brain microsomes (Toyoshima et al. 1992). The exact function of CG-], the third member of the family, has not yet been ascertained. The aim of the present study was to determine the regional location of the CG-1 gene in the human genome, by Southern blotting analysis of human-rodent somatic cell hybrid DNAs, and direct fluorescent in situ hybridization (FISH) of human metaphase chromosomes. A 979 base pair (bp) Hin dIII fragment (nucleotides 669-1643) of the CG-1 cDNA clone pCG-2 (Print et al. 1994) detected Pst Idigested human genomic DNA fragments of 5, 4.3, 3, and 2.3 kilobases (kb) which proved to be diagnostic (Fig. 1).