Partitioning Defective 6 Homolog Beta (PARD6b)

PARD6b is a member of the PAR6 family and encodes a protein with a PSD95/Discs-large/ZO1 (PDZ) domain, an OPR domain and a semi-Cdc42/Rac interactive binding (CRIB) domain. This cytoplasmic protein is involved in asymmetrical cell division and cell polarization processes as a member of a multi-protein complex.The deduced 372-amino acid protein contains a central CRIB motif and a PDZ domain. Northern blot analysis detected a 4.8-kb transcript expressed at highest levels in adult and fetal kidney, with much weaker expression in placenta, lung, and liver.The ternary complexes were formed both in vitro and in vivo. When any of the PAR6 cDNAs and aPKC were expressed with a constitutively active form of RAC in HeLa or COS-7 cells, the proteins colocalized to membrane ruffles.