hnRNP K (Heterogeneous nuclear ribonucleoprotein K) is a pre-mRNA binding protein and a component of hnRNP complexes providing substrate for pre-mRNA processing before becoming translatable mRNAs in cytoplasm. This protein containing KH domains and is ubiquitously expressed in the cytoplasm and the nucleus with a predicted molecular weight approximately 51 kD. hnRNP K expression and function are increased by epidermal growth factor (EGF). hnRNP K acts as transcriptional regulator and functions in nucleocytoplasmic shuttling, and is modified by phosphorylation (PKC delta, c-Src) and acetylation. Clone F45P9C7 has been shown to be useful for western blotting and immunohistochemistry of human, mouse, rat, rabbit and chicken hnRNP K.