Pin1 (Peptidyl-prolyl cis-trans isomerase NIMA-interacting 1; Peptidyl-prolyl isomerase, PPIase) is an enzyme that isomerizes phospho/Threonine-Proline motifs. Upon binding (to various target proteins) it can function as a protein regulator as it plays a role in post phosphorylation control.
Deregulation of PIN1 can lead to various diseases. Up-regulation is discussed to be implicated in specific cancer types, and down-regulation may be implicated in the pathogenesis Azheimer’s disease (1).
Role of Pin1 in Alzheimer’s disease
Tauopathies (such as Alzheimer’s disease) are neurodegenerative diseases associated with the pathological aggregation of microtubule-associated protein Tau, indeed hyperphosphorylated Tau is found in neurofibrillary tangles in Alzheimer’s patients. Tau phosphorylation mainly occurs at Ser/Thr sites. Recently it has been shown that Pin1 is involved in the regulation of Tau hyperphosphorylation and thus is the etiology of tautopathies (2).
Anaspec, who already provide a very broad offer for Alzheimer research (e.g. a very wide range of amyloid peptides), decided to develop the first commercial assay which enables researchers to measure the activity of Pin1. The SensoLyte® Green Pin1 Assay Kit uses a fluorogenic substrate in the cis isoform. Pin1 changes this substrate into the trans conformation, which is then readily cleaved to generate fluorescent signal. Fluorescence is monitored at Ex/Em=490/520nm. Increase in fluorescence intensity is directly proportional to the Pin1 activity. This homogeneous assay can be either used to measure the enzymatic activity of Pin1 or to detect effects of Pin1 inhibitors (see Fig. 1 and 2).
Interested in this new Pin1 assay? Interested in testing inhibiors of Pin1? If you need more information or have any comments, let me know through the form below.
1. Galas M-C., et.al., J Biol Chem 281, 28 (2006): 19296-10394.
2. Kimura T. et.al., J Biol Chem 288, 11 (2013): 7968-7977.