PCBP2

The protein encoded by this gene appears to be multifunctional. Along with PCBP-1 and hnRNPK, it is one of the major cellular poly(rC)-binding proteins. The encoded protein contains three K-homologous (KH) domains which may be involved in RNA binding. Together with PCBP-1, this protein also functions as a translational coactivator of poliovirus RNA via a sequence-specific interaction with stem-loop IV of the IRES, promoting poliovirus RNA replication by binding to its 5'-terminal cloverleaf structure. It has also been implicated in translational control of the 15-lipoxygenase mRNA, human papillomavirus type 16 L2 mRNA, and hepatitis A virus RNA. The encoded protein is also suggested to play a part in formation of a sequence-specific alpha-globin mRNP complex which is associated with alpha-globin mRNA stability. This multiexon structural mRNA is thought to be retrotransposed to generate PCBP-1, an intronless gene with functions similar to that of PCBP2. This gene and PCBP-1 have paralogous genes (PCBP3 and PCBP4) which are thought to have arisen as a result of duplication events of entire genes. This gene also has two processed pseudogenes (PCBP2P1 and PCBP2P2). Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jan 2018]

Full Name

Poly(RC) Binding Protein 2

Function

Single-stranded nucleic acid binding protein that binds preferentially to oligo dC. Major cellular poly(rC)-binding protein. Binds also poly(rU). Negatively regulates cellular antiviral responses mediated by MAVS signaling (PubMed:19881509).
It acts as an adapter between MAVS and the E3 ubiquitin ligase ITCH, therefore triggering MAVS ubiquitination and degradation (PubMed:19881509).
(Microbial infection) In case of infection by poliovirus, binds to the viral internal ribosome entry site (IRES) and stimulates the IRES-mediated translation (PubMed:12414943, PubMed:24371074).
Also plays a role in initiation of viral RNA replication in concert with the viral protein 3CD (PubMed:12414943).

Biological Process

Defense response to virusIEA:UniProtKB-KW
Innate immune responseIEA:UniProtKB-KW
IRES-dependent viral translational initiationManual Assertion Based On ExperimentIDA:UniProtKB
mRNA metabolic process1 PublicationNAS:UniProtKB
Negative regulation of defense response to virusManual Assertion Based On ExperimentIMP:UniProtKB
Positive regulation of transcription by RNA polymerase IIIEA:Ensembl
Proteasome-mediated ubiquitin-dependent protein catabolic processManual Assertion Based On ExperimentIMP:UniProtKB
Regulation of gene expressionManual Assertion Based On ExperimentIBA:GO_Central
Regulation of RNA metabolic processManual Assertion Based On ExperimentIBA:GO_Central
Viral RNA genome replicationManual Assertion Based On ExperimentIDA:UniProtKB

Cellular Location

Nucleus
Cytoplasm
Loosely bound in the nucleus. May shuttle between the nucleus and the cytoplasm.

PTM

Phosphorylated. The non-phosphorylated form(s) exhibited the strongest poly(rC)-binding activity.
(Microbial infection) Proteolyticaly cleaved by picornavirus proteinase 3CD.