Description
CIRP, also known as CIRBP (cold inducible RNA binding protein), is a 172 amino acids protein belonging to the glycine-rich RNA binding protein family, which possesses an amino-terminal RNA recognition motif, and a carboxyl-terminal glycine-rich domain consisting of several RGG motifs. CIRP is constitutively expressed in a wide variety of tissues and cells in low amounts and can be induced by cellular stresses such as cold shock, UV irradiation and hypoxia. Upon stress induction, CIRP shuttles from the nucleus to the cytoplasm to stabilize target mRNAs. CIRP might play a role in cellular processes such as transcription, translation and DNA
recombination. It acts as an RNA chaperone to facilitate translation and plays an important role in the circadian rhythm of living cells because CIRP is required for high-amplitude circadian gene expression.
Another side to the picture, it was reported that CIRP is increased and released into the bloodstream in response to hemorrhagic shock and sepsis. When CIRP triggers inflammation, it contributes to damage of organs in the body. In macrophages under hypoxic stress, CIRP translocates from the nucleus to the cytosol and is released. The activity of extracellular CIRP is mediated through the Toll-like receptor 4-myeloid differentiation factor 2 complex. In conclusion, extracellular CIRP is an endogenous proinflammatory mediator and damage associated molecular pattern (DAMP) that triggers inflammatory responses during hemorrhagic shock and
sepsis