NCBI Summary:
This intronless gene is thought to have been generated by retrotransposition of a fully processed PCBP-2 mRNA. This gene and PCBP-2 have paralogues (PCBP3 and PCBP4) which are thought to have arisen as a result of duplication events of entire genes. The protein encoded by this gene appears to be multifunctional. It along with PCBP-2 and hnRNPK corresponds to the major cellular poly(rC)-binding protein. It contains three K-homologous (KH) domains which may be involved in RNA binding. This encoded protein together with PCBP-2 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. [provided by RefSeq, Jul 2008]
General function
, Epigenetic modifications
Comment
Cellular localization
Nuclear
Comment
Ovarian function
Early embryo development
Comment
Expression regulated by
Comment
Ovarian localization
Oocyte
Comment
PCBP1 is required for maintenance of the transcriptionally silent state in fully grown mouse oocytes. Xia M et al. Global transcriptional silencing in fully grown oocytes is a critical event during mammalian oogenesis. However, how this event is regulated remains elusive. Here, we provide evidence that poly(rC)-binding protein 1 (PCBP1), a protein found by us previously to be present in metaphase II (MII) mouse oocytes, participates in maintenance of the transcriptionally silent state in fully grown mouse oocytes. Knocking down Pcbp1 by microinjection of its specific siRNAs into fully grown germinal vesicle (GV) oocytes resulted in remarkable changes in their transcriptional state, including the disequilibrium between the number of oocytes with an NSN (non-surrounded nucleolus) and those with a SN (surrounded nucleolus), and obvious transcriptional reactiviation in oocytes with a SN configuration as evidenced by BrUTP incorporation assay and immunofluorescent labeling of phosphorylated RNA polymerase II CTD and trimethylated H3 lysine 4, markers for active transcription. Furthermore, in a comprehensive microarray analysis of the preovulatory oocyte transcriptome, an incredible number of nearly 4,000 transcripts were upregulated in the Pcbp1 knockdown groups. These data indicate that lack of the function of PCBP1 disrupts the quiescent status of transcription in the fully grown oocytes, and hence supporting a role of this protein in the regulation of global transcriptional silcencing in fully grown mouse oocytes.