3sr9

Publication Abstract from PubMed

Protein tyrosine phosphatases PTP-sigma (PTPsigma) plays an important role in the development of the nervous system and nerve regeneration. Although cumulative studies about the function of PTPsigma have been reported, yet limited data have been reported about the crystal structure and in vitro activity of mouse PTPsigma. Here we report the crystal structure of mouse PTPsigma tandem phosphatase domains at 2.4 A resolution. Then we compared the crystal structure of mouse PTPsigma with human PTPsigma and found that they are very similar, superimposing with a root mean square deviation of 0.45 A for 517 equivalent Calpha atoms. But some residues in mouse PTPsigma form loops while corresponding residues in human PTPsigma form beta-sheets or alpha-helices. Furthermore, we also compared in vitro activities of mouse PTPsigma with human PTPsigma and found that mouse PTPsigma has 25-fold higher specific activity than human PTPsigma does toward O-methyl fluorescein phosphate (OMFP) as the substrate. However, there is no significant activity difference between the mouse and the human enzyme detected with p-nitrophenylphosphate (pNPP) as the substrate. Mouse PTPsigma and human PTPsigma have different substrate specificities toward OMFP and pNPP as substrates. This work gives clues for further study of PTPsigma.

Structural insights into the homology and differences between mouse protein tyrosine phosphatase-sigma and human protein tyrosine phosphatase-sigma.,Hou L, Wang J, Zhou Y, Li J, Zang Y, Li J Acta Biochim Biophys Sin (Shanghai). 2011 Dec;43(12):977-88. Epub 2011 Oct 25. PMID:22027896^[1]

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