| The clustered protocadherins (Pcdhs) are single-pass transmembrane proteins that constitute a subfamily within the cadherin superfamily. In mammals, they are arranged in three consecutive clusters named alpha, beta, and gamma. These proteins are expressed in the nervous system and are targeted to mature synapses. Interestingly, different neurons express different subsets of isoforms; however, little is known about the functions and expression of the clustered Pcdhs. Previous phylogenetic analyses that compared rodent and human clusters postulated the recent occurrence of gene duplication events. Using standard phylogenetic methods, I confirmed the prior observations, and I show that duplications are likely to occur through unequal crossing-over events... |
