PKP1
PKP1 (plakophilin 1, also known as B6P) is an armadillo-repeat protein of the beta-catenin family and a component of desmosome cell-cell junctions. It supports cell adhesion and keratinocyte differentiation, and links desmosomal cadherins to intermediate filaments. Browse Assay Genie's current range of PKP1 research reagents below, or read on for the biology behind the target.
PKP1 is a component of desmosome cell-cell junctions, which are required for positive regulation of cellular adhesion. It helps regulate the expression of desmosomal proteins and their localisation to the desmosomal plaque, which maintains cell sheet integrity and anchors desmosomes to intermediate filaments. In keratinocytes it is needed for the localisation of DSG3 and YAP1 to the cell membrane under mechanical strain, through a complex containing DSG3, YAP1, PKP1 and YWHAG. It also positively regulates keratinocyte differentiation, potentially by promoting DSG1 localisation at desmosomes, and is required for the calcium-independent development and maturation of desmosome plaques at lateral cell-cell contacts.
Beyond adhesion, PKP1 has roles at tight junctions, where it is required for the transepidermal barrier function of the skin and, in ameloblasts, facilitates TJP1/ZO-1 localisation to support Wnt-mediated proliferation and differentiation. It binds single-stranded DNA and may sense DNA damage and promote cell survival. It positively regulates cap-dependent translation by recruiting EIF4A1 to the initiation complex and promoting its ATPase activity. Through an interaction with FXR1 it may regulate the mRNA stability and protein abundance of PKP2, PKP3, DSC2 and DSP. Consistent with these roles, the protein is found in desmosomes, the nucleus, the cytoplasm, the cell membrane and stress granules.
The PKP1 gene encodes a member of the armadillo-repeat and plakophilin gene families, and the protein belongs to the beta-catenin family. Plakophilins contain numerous armadillo repeats and link cadherins to intermediate filaments in the cytoskeleton. Mutations in the gene are associated with ectodermal dysplasia/skin fragility syndrome, which is reflected in the previous HGNC name. Two transcript variants encoding different isoforms have been described. The mouse ortholog is Pkp1.
PKP1 helps recruit and stabilise desmosome components, making it central to studies of desmosome assembly and cell sheet integrity.
PKP1 positively regulates keratinocyte differentiation and supports DSG1 and DSG3 localisation, relevant to epidermal development models.
PKP1 is needed for transepidermal barrier function, and its mutations are associated with ectodermal dysplasia/skin fragility syndrome.
PKP1 recruits EIF4A1 to promote cap-dependent translation and interacts with FXR1 to influence desmosomal mRNA stability.
PKP1 is a desmosomal plaque protein that promotes cell adhesion, anchors desmosomes to intermediate filaments and supports keratinocyte differentiation. It also contributes to skin barrier function, binds single-stranded DNA and promotes cap-dependent translation by recruiting EIF4A1.
The HGNC name is plakophilin 1, and UniProt lists Plakophilin-1. B6P is an alias. The previous HGNC name was plakophilin 1 (ectodermal dysplasia/skin fragility syndrome). Two transcript variants encoding different isoforms have been reported for the gene.
Mutations in the PKP1 gene are associated with ectodermal dysplasia/skin fragility syndrome. The mouse ortholog is Pkp1. For cross-species work, check the datasheet of any product for its validated reactivity.
Other plakophilins, desmosomal cadherins and plaque proteins, and PKP1 interaction partners with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q13835; product specifications from Assay Genie datasheets.