Protocadherin Gamma B4 (PCDHgB4)

PCDHGB4 is 1 of 22 tandemly arranged genes within the PCDHG gene cluster on chromosome 5q31. The 22 PCDHG genes function as 'variable' exons that are individually spliced to a downstream constant region to form distinct PCDHG transcripts. The variable PCDHG exons encode the extracellular and transmembrane domains of the protocadherin protein, and the common region encodes the intracellular domain. To elucidate the molecular basis of fibroblast cell-cell adhesion, Matsuyoshi and Imamura (1997) investigated cadherin expression in human fibroblasts by RT-PCR using degenerate primers based on well-conserved amino acid sequences of cadherins. They isolated a partial cDNA encoding PCDHGB4, which they called FIB2. RT-PCR analysis revealed that FIB2 is expressed in fibroblasts but not in melanocytes or keratinocytes.