| Modification Notes |
Protocadherins are a subfamily of cadherins, a large group of related glycoproteins that mediate calcium-dependent cell-to-cell adhesion via a homo-philic mechanism. Involved in a variety of functions, protocadherins help to regulate neural development and synapse formation. PCDH9 (protocadherin 9) is a member of the d1-protocadherin family comprised of PCDH1, PCDH7, PCDH9 and PCDH11. Localized to the cell membrane and expressed primarily in the brain, PCDH9 is found in synaptic junctions, where it functions as a neuronal receptor involved in signal transduction and maintaining specific neuronal connections. PCDH9 contains seven cadherin domains and exists as two isoforms produced by alternative splicing. Expression of PCDH9 is found in hairy cell leukemia, a form of chronic lymphocytic leukemia. |