IDENTIFICATION OF 2 HOMOLOGOUS CYTOCHROME B(5)S IN RAT-BRAIN

Two kinds of PCR products were isolated from adult rat brain. The smal ler product matched up to liver b(5) mRNA completely. However, the lar ger one contained an additional 58 bp inserted between amino acids 96 and 97. This insertion was previously unknown and corresponded to in-f rame codons for his-ser-ala-leu and the early stop. It is assumed that these two forms arise from a primary transcript by differential mRNA processing. This finding strongly suggests that there are two homologo us b(5)s expressed in rat brain. (C) 1997 Academic Press.