Lysine residues within the PTP motif: (HCKAGKGR; lysines in bold) in addition to a His residue inside the WPD loop (Lee et al., 1999). Interestingly, the PTP motif of Cdc14 (HCKAGLGR) can also be reminiscent of PTEN, though the His residue of your WPD loop of PTEN is actually a glycine (Gly288) in Cdc14, and for that reason it is actually unlikely that Cdc14 functions to dephosphorylate lipid substrates. TheC.H.Gray et al.Fig. three. Structural relatedness of your A and Bdomains of Cdc14B. (A) Comparison of structures on the A and Bdomains of Cdc14B along with the phosphatase domain of PTEN. In the upper panel, the 3 domains are shown inside the very same orientation, and a stereoview of the Adomain (green) and Bdomain (blue) superimposed is shown within the decrease panel. (B) Structurebased sequence alignment of domains A and B of Cdc14B. Equivalent secondary structural elements are suf ed with `A’ and `B’ for domains A and B, respectively.most closely associated protein phosphatases to Cdc14 are kinaseassociated phosphatase (KAP) (Song et al., 2001) and vaccinia H1related phosphatase (VHR) (Yuvaniyama et al., 1996) (Table II).The Adomain features a DSPlike foldThe 3D architecture with the Adomain (residues 4498) bears a exceptional resemblance to the Bdomain of Cdc14. As shown in Lovastatin hydroxy acid (sodium) Protocol Figure 3A, the secondary structural elements in the Adomain superimpose closely onto the conserved core components of your Bdomain, along with the two domains share exactly the same secondary structure topology andpolypeptide connectivities. General, the Ca atoms of 119 equivalent residues superimpose inside an r.m.s.d. of 2.six A along with the Zscore, a measure in the structural similarity in standard deviations above the expected value between two molecules, is 9.6 (Table II). Interestingly, this evaluation indicated that the PTP/DSP household is structurally one of a kind, such that a equivalent topology will not take place in other proteins. These dings suggest that the Adomain of Cdc14 resulted from divergent evolution from an ancestral PTP/DSP family member, possibly from a gene duplication event of the current catalytically active Bdomain.Cdc14B will not be re cted in any sequence similarity. A structurebased alignment with the A and Bdomains indicates only 11 sequence identity (Figure 3B). Importantly, none in the catalytic site residues, including the catalytic web site Cys and Arg residues, characteristic of PTP/DSPs, is present in the Adomain. Signi antly, the structure of the Adomain suggests that it could be unable to bind phosphate within the equivalent region from the molecule to the phosphatebinding cradle formed by the PTP signature motif with the Bdomain. In the Adomain, an insertion of two residues in the Nterminus of a4A, equivalent for the a4B helix which forms the base of your catalytic website inside the Bdomain (Figure 3B), alters the conformation of the Adomain to ensure that it no longer forms a phosphatebinding cradle. Consistent with the notion that the Adomain is incapable of binding a phosphate moiety, we observed tungstate at 25 mM bound only towards the catalytic web site of your Bdomain. Other variations in between the A and Bdomains include things like a 13 residue insertion within the a5A/a6A loop, which contributes towards the peptidebinding groove, along with the counterpart to the WPD loop in the Bdomain is 4 residues longer within the Adomain (Figure 3B). Ultimately, there are no equivalents of the a1 and a2 helices, and b4 strand, conserved within the Bdomain of Cdc14B along with other DSPs.The peptidebinding groove is selective for prolinedirected peptidesA distinctive function with the catalytic web page of Cdc14B is its place withi.
