ISOLATION AND CHARACTERIZATION OF BART-1 - A NOVEL BALLOON ANGIOPLASTY RESPONSIVE TRANSCRIPT IN RAT CAROTID ARTERIES

In previous studies, differential display analysis of balloon angiopla sty-damaged rat carotid arteries identified a temporally expressed par tial cDNA termed RC9. This message is undetectable in undamaged vessel s, reaches maximal levels 3 days post-procedure, and reduces to half-m aximal expression by 14 days post angioplasty, Using RC9 to screen a c DNA library, we now report the isolation and characterization of a ful l-length clone, termed BART-1, BART-1 is 98% homologous to RC9 and sho ws the same mRNA expression pattern as RC9 in rat carotid arteries sub ject to balloon angioplasty, Northern analysis of various rat tissues reveals tissue specificity and possible differential processing, Neith er the nucleic acid nor amino acid sequences demonstrate similarity to previously reported expressed sequences, Predicted amino acid analysi s reveals two strongly hydrophilic and one hydrophobic region, suggest ing a type II integral membrane protein, The cDNA sequence hybridized to genomic DNA from a variety of species, suggesting evolutionary cons ervation, Thus, BART-1 mRNA appears to represent an inducible, tissue- specific transcript encoding a putative integral membrane protein tran siently expressed in response to vascular trauma.