Haspin (germ cell associated 2), EC 188.8.131.52, is a serine/threonine kinase that has a critical function in mitosis. The enzyme is localized to chromosomes and phosphorylates threonine-3 on histone H3 during mitosis. Phosphorylation of T3 opens up a binding site for the chromosomal passenger complex and activates Aurora B kinase at the centromere. This enables proper chromatid cohesion and metaphase alignment, ensuring normal progression through the cell cycle.
Haspin is a constitutively active enzyme. Studies have shown that during interphase haspin is autoinhibited by a conserved segment of basic residues (haspin basic inhibitory segment or HBIS) within the N-terminal domain, immediately upstream from the kinase domain. The enzyme is reactivated in M phase by Cdk1 phosphorylation of the N-terminus. Phosphorylation leads to recruitment of Polo-like kinase-1 (PLK-1), which further phosphorylates the N-terminal domain of haspin. In addition, the localization of Aurora B kinase to the centromere creates a positive feedback loop that further increases haspin activity.
Haspin is highly expressed in proliferating cells, so is a potential target for cancer therapy. Inhibition of the enzyme has been shown to suppress proliferation of cancer cells both in vitro and in vivo. Haspin is also of interest in spermatogenesis as it is highly expressed in testes.
To view external sources of pharmacological information for Haspin, please click here: IUPHAR Receptor CodeView all products for Haspin »
|Gene||Species||Gene Symbol||Gene Accession No.||Protein Accession No.|
|Germ cell associated 2 (haspin)||Human||GSG2||NM_031965||Q8TF76|
Literature for Haspin
A collection of over 400 products for kinase research, the listing includes inhibitors of:
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- MAPK Signaling
- Receptor Serine/Threonine Kinases
In normal cells, each stage of the cell cycle is tightly regulated, however in cancer cells many genes and proteins that are involved in the regulation of the cell cycle are mutated or over expressed. Adapted from the 2015 Cancer Product Guide, Edition 3, this poster summarizes the stages of the cell cycle and DNA repair. It also highlights strategies for enhancing replicative stress in cancer cells to force mitotic catastrophe and cell death.Request copy | Download PDF | View all posters