The Specific Expression of Three Novel Splice Variant Forms of Human Metalloprotease-like Disintegrin-like Cysteine-rich Protein 2 Gene in Brain Tissues and Glioma

Surgery and Science, Gradu-ate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582We have previously identified 67 exons on a yeast artificial chromosome contig spanning 1.5 Mbaround the multidrug resistance 1 gene region of human chromosome 7q21.1. In this study,we identified three novel cytoplasmic variants (MDC2-γ, MDC2-δ, and MDC2-e) of the humanmetalloprotease-like disintegrin-like cysteine-rich protein 2 (MDC2) among these exons by screeninga human brain cDNA library and also by using a reverse transcription polymerase chain reaction.Genomic sequence analysis strongly supported the idea that the variations in the cytoplasmicdomain were generated by alternative splicing. The expression of MDC2 variant forms in humanbrain tissue and gliomas was examined by reverse transcription polymerase chain reaction andRNase protection assay. MDC2-e was expressed only in the cortical and hippocampal regions inhuman brain, but not in gliomas. In contrast, MDC2-γ was a major form expressed in humangliomas. Specific expression of these cytoplasmic variants of MDC2 in human brain and its malig-nancies is discussed.Key words: MDC — ADAM — Alternative splicing — MDR region