Multiple splicing variants of two new human ATP-binding cassette transporters, ABCC11 and ABCC12

Two new human ABC transporters, ABCC11 and ABCC12, were cloned from a cDNA library of human adult liver. ABCC11 and ABCC12 genes consist of 30 and 29 exons, respectively, and they are tandemly located in a tail-to-head orient ation on human chromosome 16q12.1. The predicted amino acid sequences of bo th gene products show a high similarity with ABCC5. The transcripts of ABCC 11 and AECC12 genes were detected by PCR in various adult human tissues, in cluding liver, lung, and kidney, and also in several fetal tissues. By sear ching cDNA libraries from various human tissues, we have identified alterna tive splicing variants of ABCC11 and ABCC12 genes at significantly high fre quencies. One splice variant lacking the exon 28 corresponded to about 25% of total ABCC11 gene transcripts. Furthermore, four splicing variants encod ing putatively short peptides were predominant in ABCC12 gene transcripts. Those splicing variants may represent diverse biological functions of these ABC transporter genes. (C) 2001 Academic Press.