A Disintegrin And Metalloprotease 23 (ADAM23)

The cellular disintegrins, also known as ADAM and MDC proteins, are a class of potential cell adhesion molecules. By searching an EST database for sequences related to MDC, Sagane et al. (1998) identified a partial MDC3 cDNA. They screened a human brain cDNA library and used 3-prime RACE to clone additional cDNAs corresponding to the entire MDC3 coding region. The predicted 832-amino acid protein contains the typical cellular disintegrin domains. However, the zinc-binding motif, which is critical for proteinase activity, is disrupted in MDC3 as well as the other MDC proteins. MDC3 shares approximately 52% sequence similarity with MDC and MDC2. Northern blot analysis revealed that MDC3 was expressed predominantly in brain as several transcripts ranging in size from 3.5 to 7 kb.