Studying the Functions of PP1 in Mitosis with PDPs

In order to replicate, cells need to duplicate their chromosomes and then separate the identical sets before the cell divides into two. The process of separation of these identical sets of chromosomes is called mitosis. The so-called histones are proteins that package DNA and are part of chromosomes. At the end of mitosis, the holoenzyme complex of PPl and the histone H3-PPl-targeting subunit Repo-Man dephosphorylates histone H3 on threonine 3 (H3T3), which is phosphorylated during mitosis [29]. The effects of PDP3-induced PPl activation on the phosphorylation status of H3T3 and downstream effects were systematically studied [16]. 

Protein phosphorylation is one of the most important posttranslational modifications for cellular functions and signal transduction. As the phosphorylation state of a protein is controlled by the kinase and the phosphatase, modulators of kinases and phosphatases are valuable tools to study their functions. Compared to the large amount of kinase modulators, the development of phosphatase modulators is still limited and challenging. Over the years, protein phosphatases have been notoriously difficult to study. 

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