CDNA CLONING, CHROMOSOMAL LOCALIZATION, AND EXPRESSION PATTERN OF EPLG8, A NEW MEMBER OF THE EPLG GENE FAMILY ENCODING LIGANDS OF EPH-RELATED PROTEIN-TYROSINE KINASE RECEPTORS

By screening a human fetal brain cDNA library under low stringency usi ng cDNA encoding the mouse ligand of Cek5 as a probe, we have isolated a novel cDNA belonging to the EPLG gene family. This family encodes l igands of EPH-related tyrosine kinase receptors. Since the novel gene is the eighth member of the EPLG gene family, it is designated EPLG8. The deduced amino acid sequence of EPLG8 suggests that it encodes a tr ansmembrane protein that is most related to those encoded by EPLG2 and EPLG5. We mapped the EPLG8 gene to human chromosome 17p11.2-p13.1 by PCR screening of human-rodent somatic cell hybrid panels. In the midte rm fetus, EPLG8 mRNA is expressed at the highest level in brain, follo wed by heart, kidney, and lung. In the adult, EPLG8 mRNA expression is restricted to brain. These data suggest that LERK-8, the protein enco ded by EPLG8, is important in brain development as well as in its main tenance. Moreover, since levels of EPLG8 expression were particularly high in several forebrain subregions compared to other brain subregion s, LERK-8 may play a pivotal role in forebrain function. (C) 1997 Acad emic Press.