KH domain containing, RNA binding, signal transduction associated protein 1 (p21 Ras GTPase-activating protein-associated p62, GAP-associated tyrosine phosphoprotein p62, src-associated in mitosis 68 kD protein, Sam68, p68, KHDRBS1)

Function

• recruited & tyrosine phosphorylated by:
  • tyrosine kinase receptors
    • T-cell receptor, leptin receptor, insulin receptor
  • non-receptor tyrosine kinases
    • LCK, FYN JAK3
• tyrosine phosphorylated form functions as an adapter protein in signal transduction by binding to SH2 & SH3 domain- containing proteins
• role in G2-M progression in the cell cycle
• phosphorylated on Tyr during mitosis
• binds to src through pTyr-SH2 interaction
• may be sequestered in the nucleus of interphase cells
  • able to interact with src only after breakdown of the nuclear envelope
• represses CBP-dependent transcriptional activation
• putative regulator of mRNA stability
• mediates mRNA nuclear export
• tyrosine phosphorylation negatively regulates RNA binding
• isoform 3 is only expressed in growth-arrested cells
  • inhibits S phase entry

Structure

• self-associates to form homo-oligomers when bound to RNA
• KH domain is required for binding to RNA
• acetylatation needed for RNA-binding

Alternative splicing

named isoforms=3

Expression

ubiquitously expressed in all tissue examined

More general terms

• phosphoprotein

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=10657
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:10657
• OMIM: https://mirror.omim.org/entry/602489
• UniProt: http://www.uniprot.org/uniprot/Q07666.html