Structure of the human CpG-island-containing lung Kruppel-like factor (LKLF) gene and its location in chromosome 19p13.11-13 locus

We have cloned earlier a short human genomic fragment which showed strong s imilarity with the mouse cDNA encoding lung Kruppel-like zinc finger transc ription factor (LKLF), predominantly expressed in mouse developing lung, sp leen, and vascular system, which might play a key role in programming the q uiescent state of single positive T cells and blood vessel wall morphogenes is. Here we report the successful cloning of the human LKLF cDNA, its genom ic structure and chromosomal localization at the 19p13.11-p13.13 locus. The full-length human LKLF cDNA has longer 5'-UTR with higher GC content than mouse cDNA and encodes a predicted protein of 355 amino acids which has thr ee zinc fingers at the C-terminus and a proline-rich N-terminal domain. Hum an and mouse proteins share 87.3% identity and 90.2% amino acid similarity. The human LKLF gene consists of three exons. From the proximal promoter to the end of the second exon, we have found a CpG island with an average 76% GC content and two regions of unusually high GC density. (C) 1999 Federati on of European Biochemical Societies.