PABPC4

Polyadenylate-binding protein 4 is a is_associated_with::protein that in humans is encoded by the PABPC4 is_associated_with::gene.

Function
Poly(A)-binding proteins (PABPs) bind to the poly(A) tail present at the 3-prime ends of most eukaryotic mRNAs. PABPC4 or IPABP (inducible PABP) was isolated as an activation-induced T-cell mRNA encoding a protein. Activation of T cells increased PABPC4 mRNA levels in T cells approximately 5-fold. PABPC4 contains 4 RNA-binding domains and proline-rich C terminus. PABPC4 is localized primarily to the cytoplasm. It is suggested that PABPC4 might be necessary for regulation of stability of labile mRNA species in activated T cells. PABPC4 was also identified as an antigen, APP1 (activated-platelet protein-1), expressed on thrombin-activated rabbit platelets. PABPC4 may also be involved in the regulation of protein translation in platelets and megakaryocytes or may participate in the binding or stabilization of polyadenylates in platelet dense granules.

Model organisms
is_associated_with::Model organisms have been used in the study of PABPC4 function. A conditional is_associated_with::knockout mouse line, called Pabpc4tm1a(KOMP)Wtsi was generated as part of the is_associated_with::International Knockout Mouse Consortium program — a high-throughput mutagenesis project to generate and distribute animal models of disease to interested scientists.

Male and female animals underwent a standardized is_associated_with::phenotypic screen to determine the effects of deletion. Twenty tests were carried out on is_associated_with::mutant mice and one significant abnormality was observed: female homozygous mutants displayed is_associated_with::impaired glucose tolerance.

Interactions
PABPC4 has been shown to interact with is_associated_with::PHLDA1.