Maternal embryonic leucine zipper kinase (MELK) is an enzyme that in humans is encoded by the MELKgene. MELK is a serine/threonine kinase belonging to the family of AMPK/snf1 protein kinases. MELK was first identified present as maternal mRNA in mouse embryos. MELK has been shown to involved in progression through the cell cycle, possibly linked to its interaction with CDC25B.
MELK expression is elevated in a number of cancers and is an active research target for pharmacological inhibition. MELK was previously believed to be essential for cancer cell proliferation. However, recent research using CRISPR has demonstrated that MELK is fully dispensable for cancer cell growth, casting doubt on the rationale for targeting this protein in patients.
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