Tyrosine kinase

Protein tyrosine kinase
pdb 2HCK, rendered in PyMOL
Identifiers
SymbolPkinase_Tyr
PfamPF07714
InterProIPR001245
SMARTTyrKc
PROSITEPDOC00629
SCOP21apm / SCOPe / SUPFAM
OPM superfamily186
OPM protein2k1k
CDDcd00192
Membranome3
Available protein structures:
Pfam  structures / ECOD  
PDBRCSB PDB; PDBe; PDBj
PDBsumstructure summary

A tyrosine kinase is an enzyme that can transfer a phosphate group from ATP to the tyrosine residues of specific proteins inside a cell. It functions as an "on" or "off" switch in many cellular functions.

Tyrosine kinases belong to a larger class of enzymes known as protein kinases which also attach phosphates to other amino acids such as serine and threonine. Phosphorylation of proteins by kinases is an important mechanism for communicating signals within a cell (signal transduction) and regulating cellular activity, such as cell division.

Protein kinases can become mutated, stuck in the "on" position, and cause unregulated growth of the cell, which is a necessary step for the development of cancer. Therefore, kinase inhibitors, such as imatinib and osimertinib, are often effective cancer treatments.

Most tyrosine kinases have an associated protein tyrosine phosphatase, which removes the phosphate group.