PARD6G (partitioning defective 6 homolog gamma) is a 376 amino acid adaptor protein that is involved in cell polarization and asymmetrical cell division processes. PARD6G contains one OPR domain, one PDZ (DHR) domain and one pseudo-CRIB domain. The PDZ and pseudo-CRIB domains are required for interaction with Rho small GTPases. Through its complex formation with PARD3G, PARD6G participates in the linking of GTP-bound Rho small GTPases to atypical protein kinase C (PKC) proteins. This assembly is involved in formation of normal tight junctions at epithelial cell-cell contacts. When atypical PKC and PARD6G are expressed with a constitutively active RAC, the proteins colocalize to the membrane ruffles, which are structures that occur at the leading edge of polarized cells during movement. Though widely expressed, PARD6G is found at highest levels in adult and fetal kidney.