Poly(rC)-binding protein 2 is a protein that in humans is encoded by the PCBP2 gene. [5]
The protein encoded by this gene appears to be multifunctional. It along with PCBP-1 and hnRNPK corresponds to the major cellular poly(rC)-binding proteins. It contains three K-homologous (KH) domains which may be involved in RNA binding. This encoded protein together with PCBP-1 also functions as translational coactivators of poliovirus RNA via a sequence-specific interaction with stem-loop IV of the IRES and promote 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 intronless gene which has similar functions. This gene and PCBP-1 has paralogues PCBP3 and PCBP4 which is thought to arose as a result of duplication events of entire genes. It also has two processed pseudogenes PCBP2P1 and PCBP2P2. There are presently two alternatively spliced transcript variants described for this gene. [6]
In humans, the PCBP2 gene overlaps with TUC338, a transcribed ultra-conserved element implicated in Hepatocellular carcinoma. [7]
PCBP2 has been shown to interact with HNRPK, [8] PTBP1, and HNRNPL. [8]
Gideon Dreyfuss is an American biochemist, the Isaac Norris Professor of Biochemistry and Biophysics at the University of Pennsylvania School of Medicine, and an investigator of the Howard Hughes Medical Institute. He was elected to the National Academy of Sciences in 2012.
The K Homology (KH) domain is a protein domain that was first identified in the human heterogeneous nuclear ribonucleoprotein (hnRNP) K. An evolutionarily conserved sequence of around 70 amino acids, the KH domain is present in a wide variety of nucleic acid-binding proteins. The KH domain binds RNA, and can function in RNA recognition. It is found in multiple copies in several proteins, where they can function cooperatively or independently. For example, in the AU-rich element RNA-binding protein KSRP, which has 4 KH domains, KH domains 3 and 4 behave as independent binding modules to interact with different regions of the AU-rich RNA targets. The solution structure of the first KH domain of FMR1 and of the C-terminal KH domain of hnRNP K determined by nuclear magnetic resonance (NMR) revealed a beta-alpha-alpha-beta-beta-alpha structure. Autoantibodies to NOVA1, a KH domain protein, cause paraneoplastic opsoclonus ataxia. The KH domain is found at the N-terminus of the ribosomal protein S3. This domain is unusual in that it has a different fold compared to the normal KH domain.
Heterogeneous nuclear ribonucleoprotein A1 is a protein that in humans is encoded by the HNRNPA1 gene. Mutations in hnRNP A1 are causative of amyotrophic lateral sclerosis and the syndrome multisystem proteinopathy.
Heterogeneous nuclear ribonucleoprotein K is a protein that in humans is encoded by the HNRNPK gene. It is found in the cell nucleus that binds to pre-messenger RNA (mRNA) as a component of heterogeneous ribonucleoprotein particles. The simian homolog is known as protein H16. Both proteins bind to single-stranded DNA as well as to RNA and can stimulate the activity of RNA polymerase II, the protein responsible for most gene transcription. The relative affinities of the proteins for DNA and RNA vary with solution conditions and are inversely correlated, so that conditions promoting strong DNA binding result in weak RNA binding.
Heterogeneous nuclear ribonucleoproteins A2/B1 is a protein that in humans is encoded by the HNRNPA2B1 gene.
Heterogeneous nuclear ribonucleoprotein U is a protein that in humans is encoded by the HNRNPU gene.
Poly(rC)-binding protein 1 is a protein that in humans is encoded by the PCBP1 gene.
Heterogeneous nuclear ribonucleoprotein D0 (HNRNPD) also known as AU-rich element RNA-binding protein 1 (AUF1) is a protein that in humans is encoded by the HNRNPD gene. Alternative splicing of this gene results in four transcript variants.
Heterogeneous nuclear ribonucleoproteins C1/C2 is a protein that in humans is encoded by the HNRNPC gene.
Synaptotagmin-binding, cytoplasmic RNA-interacting protein (SYNCRIP), also known as heterogeneous nuclear ribonucleoprotein (hnRNP) Q or NS1-associated protein-1 (NSAP-1), is a protein that in humans is encoded by the SYNCRIP gene. As the name implies, SYNCRIP is localized predominantly in the cytoplasm. It is evolutionarily conserved across eukaryotes and participates in several cellular and disease pathways, especially in neuronal and muscular development. In humans, there are three isoforms, all of which are associated in vitro with pre-mRNAs, mRNA splicing intermediates, and mature mRNA-protein complexes, including mRNA turnover.
Heterogeneous nuclear ribonucleoprotein F is a protein that in humans is encoded by the HNRNPF gene.
Polyadenylate-binding protein 2 (PABP-2) also known as polyadenylate-binding nuclear protein 1 (PABPN1) is a protein that in humans is encoded by the PABPN1 gene. PABN1 is a member of a larger family of poly(A)-binding proteins in the human genome.
Heterogeneous nuclear ribonucleoprotein H is a protein that in humans is encoded by the HNRNPH1 gene.
Heterogeneous nuclear ribonucleoprotein L is a protein that in humans is encoded by the HNRNPL gene.
Heterogeneous nuclear ribonucleoprotein A/B, also known as HNRNPAB, is a protein which in humans is encoded by the HNRNPAB gene. Although this gene is named HNRNPAB in reference to its first cloning as an RNA binding protein with similarity to HNRNP A and HNRNP B, it is not a member of the HNRNP A/B subfamily of HNRNPs, but groups together closely with HNRNPD/AUF1 and HNRNPDL.
Far upstream element-binding protein 2 is a protein that in humans is encoded by the KHSRP gene.
Heterogeneous nuclear ribonucleoprotein R is a protein that in humans is encoded by the HNRNPR gene.
Poly(rC)-binding protein 4 is a protein that in humans is encoded by the PCBP4 gene.
Poly(rC)-binding protein 3 is a protein that in humans is encoded by the PCBP3 gene.
Putative RNA-binding protein Luc7-like 1 is a protein that in humans is encoded by the LUC7L gene.