Partitioning defective protein 6, PB1 domain (IPR034868)

Short name: PB1_Par6

Overlapping homologous superfamilies


Domain relationships

  • PB1 domain (IPR000270)
    • Partitioning defective protein 6, PB1 domain (IPR034868)


PAR-6 is essential for asymmetric division of the Caenorhabditis elegans zygote and for cell polarization in the Drosophila embryo [PMID: 8898226, PMID: 9834192, PMID: 11146625]. Mammalian Par6 binds to Par3 and aPKC, as well as to the small GTPase Cdc42, to form a complex which is a major cell polarity regulator [PMID: 23535009]. This complex has been implicated in the formation of tight junctions (TJ) in mammalian epithelial cells. Whereas only one par-6 gene exists in Drosophila and C. elegans, a family of four is present in mammals, designated as Par6A-D [PMID: 10934474], although no full-length clone of Par6D has yet been identified. Par6 isoforms A-C localize differently when expressed in MDCK epithelial cells and have distinct effects on TJ formation [PMID: 15292221].

Par6 contains an N-terminal PB1 domain, a C-terminal PDZ domain and a semi-CRIB motif immediately preceding the PDZ domain. The PB1 domain of Par6 forms a hetero-dimer with the PB1 domain of aPKC [PMID: 23535009].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.