pleckstrin homology domain-containing family O member 1 (casein kinase 2-interacting protein 1, CK2-interacting protein-1, CKIP-1, c-Jun-binding protein, JBP, PLEKHO1, CKIP1, OC120, HQ0024c)

Function: - role in the regulation of the actin cytoskeleton through its interactions with actin capping protein - may function to target CK2 & ATM to the plasma membrane thus serving as an adapter to facilitate the phosphorylation of actin capping protein by protein kinase 2 (CK2) - appears to inhibit tumor cell growth by inhibiting AKT-mediated cell-survival - implicated in PI3K-regulated muscle differentiation, the regulation of AP-1 activity (plasma membrane bound AP-1 regulator that translocates to the nucleus) & the promotion of apoptosis induced by tumor necrosis factor TNF - heterodimer or homodimer - interacts with CK2 & actin capping subunits (capping protein CP-alpha & CP-beta) - CKIP1 & CK2 together inhibit the activity of actin capping protein at the barbed ends of actin filaments - interacts with ATM, IFP35, JUN, JUND, NMI & PI3K - C-terminal fragments could be released during apoptosis via caspase-3-dependent cleavage Structure: contains 1 PH domain Compartment: - membrane, nucleus - predominantly localized to the plasma membrane - in C2C12 cells, with the absence of growth factor, it is found in the nucleus - rapidly translocates to the plasma membrane after insulin stimulation - in response to TNF, translocates from the plasma membrane to the cytoplasm & then to the nucleus accompanied by cleavage by caspase-3 - subcellular location is highly dependent on cell type - found exclusively at plasma membrane, in some cells Alternative splicing: named isoforms=2 Expression: - expressed in skeletal muscle & heart > kidney, liver, brain & placenta > pancreas & lung - up-regulated by IFN-gamma & IL2 or in C2C12 cells Pathology: - detected in cancer cell lines including as MOLT-4, HEK293 & Jurkat cells

General

cytoskeletal protein pleckstrin homology domain containing family

Properties

SIZE: entity length = 409 aa MW = 46 kD COMPARTMENT: cytoplasm MOTIF: PH domain {21-132} capping proteins (CPs) interaction {133-193} ATM, CKIP, IFP35 and NMI interaction {136-308} MOTIF: binding site SITE: 155-155 FOR-BINDING-OF: Capping protein binding site SITE: 157-157 FOR-BINDING-OF: Capping protein Negative regulator of AP-1 activity {308-409} MOTIF: proteolytic site {310-311} proteolytic site {345-346}

Database Correlations

OMIM 608335 UniProt Q53GL0 Pfam PF00169

References

UniProt :accession Q53GL0