Overview:

TOPK is a MAPK kinase that phosphorylates p38 MAPK and is activated in a cell-cycle-dependent manner in neuronal progenitor cells in vitro (1). Expression of TOPK is detected in male germ line progenitor cells, activated T-cells, and a variety of lymphomas and leukemias. In vitro studies have shown that activated TOPK phosphorylated p38MAPK but not JNK or ERK. TOPK activation requires phosphorylation by both the M-phase CDK1/CyclinB kinase complex and another unknown kinase, possibly RafC or RafA. TOPK may play an important role in linking extracellular signals to an intracellular state, possibly allowing extracellular influence on the cell-cycle-related processes of proliferation or differentiation (2).

Gene Aliases:

PBK, SPK, Nori-3, FLJ14385

Genbank Number:

NM_018492

References:

1. Matsumoto, S. et al: Characterization of a MAPKK-like protein kinase TOPK. Biochem Biophys Res Commun. 2004; 325: 997-1004.

2. Simons-Evelyn, M. et al: PBK/TOPK is a novel mitotic kinase which is upregulated in Burkitt's lymphoma and other highly proliferative malignant cells. Blood Cells Mol Dis, 2001; 27: 825-829.