2j16
APO & SULPHATE BOUND FORMS OF SDP-1APO & SULPHATE BOUND FORMS OF SDP-1
Structural highlights
Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedReactive oxygen species trigger cellular responses by activation of stress-responsive mitogen-activated protein kinase (MAPK) signalling pathways. Reversal of MAPK activation requires the transcriptional induction of specialized cysteine-based phosphatases that mediate MAPK dephosphorylation. Paradoxically, oxidative stresses generally inactivate cysteine-based phosphatases by thiol modification and thus could lead to sustained or uncontrolled MAPK activation. Here we describe how the stress-inducible MAPK phosphatase, Sdp1, presents an unusual solution to this apparent paradox by acquiring enhanced catalytic activity under oxidative conditions. Structural and biochemical evidence reveals that Sdp1 employs an intramolecular disulphide bridge and an invariant histidine side chain to selectively recognize a tyrosine-phosphorylated MAPK substrate. Optimal activity critically requires the disulphide bridge, and thus, to the best of our knowledge, Sdp1 is the first example of a cysteine-dependent phosphatase that couples oxidative stress with substrate recognition. We show that Sdp1, and its paralogue Msg5, have similar properties and belong to a new group of phosphatases unique to yeast and fungal taxa. Redox-mediated substrate recognition by Sdp1 defines a new group of tyrosine phosphatases.,Fox GC, Shafiq M, Briggs DC, Knowles PP, Collister M, Didmon MJ, Makrantoni V, Dickinson RJ, Hanrahan S, Totty N, Stark MJ, Keyse SM, McDonald NQ Nature. 2007 May 24;447(7143):487-92. Epub 2007 May 9. PMID:17495930[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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