2pk9

Publication Abstract from PubMed

The ability to sense and respond appropriately to environmental changes is a primary requirement of all living organisms. In response to phosphate limitation, Saccharomyces cerevisiae induces transcription of a set of genes involved in the regulation of phosphate acquisition from the ambient environment. A signal transduction pathway (the PHO pathway) mediates this response, with Pho85-Pho80 playing a vital role. Here we report the X-ray structure of Pho85-Pho80, a prototypic structure of a CDK-cyclin complex functioning in transcriptional regulation in response to environmental changes. The structure revealed a specific salt link between a Pho85 arginine and a Pho80 aspartate that makes phosphorylation of the Pho85 activation loop dispensable and that maintains a Pho80 loop conformation for possible substrate recognition. It further showed two sites on the Pho80 cyclin for high-affinity binding of the transcription factor substrate (Pho4) and the CDK inhibitor (Pho81) that are markedly distant to each other and the active site.

Structure of the Pho85-Pho80 CDK-cyclin complex of the phosphate-responsive signal transduction pathway.,Huang K, Ferrin-O'Connell I, Zhang W, Leonard GA, O'Shea EK, Quiocho FA Mol Cell. 2007 Nov 30;28(4):614-23. PMID:18042456^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.