Molecular cloning of a novel 130-kDa cytoplasmic protein, Ankhzn, containing ankyrin repeats hooked to a zinc finger motif

A novel gene was trapped in mouse embryonic stem cells with a promoterless gene trap vector. Fused transcripts were isolated from the embryos by rapid amplification of cDNA ends, which were used for full-length cDNA cloning. The protein predicted from the cDNA consisting of 7143 nucleotides comprise s 1184 amino acids, which was confirmed by in vitro transcription/translati on assaying An antibody against the synthesized peptide reacted with an app roximate 130-kDa protein on SDS-PAGE. A search of available databases revea led that this protein is a novel protein composed of 17 ankyrin repeats hoo ked to a zinc finger motif, which we named Ankhzn. Ankhzn was observed on t he endosomal membrane on immunoelectron microscopic analysis. Ankhzn belong s to a new subgroup of double zinc finger proteins which may be involved in vesicle or protein transport. Ankhzn mRNA and its protein were expressed u biquitously from embryonic day 10.5 to adulthood. (C) Academic Press.