Isolation, cloning, and characterization of a novel rat lung zinc finger gene, RLZF-Y

Zinc-finger (ZF) proteins are widely distributed. The current study reports isolation, cloning and characterization of a novel ZF gene, RLZF-Y. Total RNA from rat lung was reverse transcribed. The 5' and 3' ends were isolated by rapid amplification of cDNA ends (RACE) using primers derived from a previously isolated partial clone. RACE products of 1.5 and 1.1 kb were cloned and sequenced. Identical overlapping sequence of 70 base pairs confirmed representation of the same cDNA approximately 2.5 kb in length. Probes derived from both 5' RACE and 3' RACE products independently hybridized to a 2.5 kb mRNA from rat lung. RLZF-Y mRNA is expressed in lung, brain, heart and kidney; expression is low in liver. Predicted amino acid sequence analysis defined three regions of similarity to known C2H2 ZF proteins: a region containing seven ZF structures characteristic of the Krüppel-like subfamily of ZF genes; a region with sequence similarity to the Krüppel-associated box A (KRAB-A) domain at the amino end; an amino-terminal leucine-rich region (LeR) adjacent to KRAB-A. The presence of KRAB-A and the adjacent LeR implies RLZF-Y protein may function as a transcriptional repressor.