{PDOC51436} {PS51436; POTYVIRUS_NIA_PRO} {BEGIN} *************************************************** * Potyvirus NIa protease (NIa-pro) domain profile * *************************************************** Tobacco etch virus (TEV), tomato vein mottling virus (TVMV), and plum pox virus (PPV) are members of the Potyviridae family [E1]. The potyvirus genome is a (+) stranded RNA and is translated into a single polyprotein upon infection, which is processed by the virally encoded proteases P1, HC-Pro, and NIa. Most of the cleavage events are performed by NIa (nuclear inclusion protein a) protease (NIa-pro). NIa-pro processes seven sites present in the potyvirus polyprotein, named as A, B, C, D, V, E, and F. NIa-pros obtained from potyviruses have similar structures and functions. The potyvirus NIa-pro has a His-Asp-Cys catalytic triad, which is homologous to the trypsin-like proteases (see ) except for Cys replacing Ser. NIa-pros obtained from potyviruses share certain sequence identities; however they recognize distinct amino acid sequences at each recognition sites. Consequently, they cannot recognize the cleavage sites of each other efficiently [1]. Nia-pro belongs to peptidase family C4 [E2]. In addition to the catalytic activity NIa-pro possesses also sequence non-specific RNA-binding activity and RNA polymerase (NIb) binding activity [3]. The potyvirus NIa protein contains the following two domains; the VPg domain at the N-terminus and the NIa-pro domain at the C-terminus [1,2]. The ~250- amino acid NIaPro domain adopts the characteristic two-domain antiparallel beta-barrel fold that is the hallmark of trypsin-like serine proteases, with the catalytic triad residues His, Asp, and Cys located at the interface between domains (see ) [3]. The profile we developed covers the entire potyvirus NIa-pro domain. -Sequences known to belong to this class detected by the profile: ALL. -Other sequence(s) detected in Swiss-Prot: NONE. -Last update: August 2011 / First entry. [ 1] Zheng N., Perez J. de J., Zhang Z., Dominguez E., Garcia J.A., Xie Q. "Specific and efficient cleavage of fusion proteins by recombinant plum pox virus NIa protease." Protein Expr. Purif. 57:153-162(2008). PubMed=18024078; DOI=10.1016/j.pep.2007.10.008 [ 2] Daros J.-A., Carrington J.C. "RNA binding activity of NIa proteinase of tobacco etch potyvirus." Virology 237:327-336(1997). PubMed=9356344; DOI=10.1006/viro.1997.8802 [ 3] Phan J., Zdanov A., Evdokimov A.G., Tropea J.E., Peters H.K. III, Kapust R.B., Li M., Wlodawer A., Waugh D.S. "Structural basis for the substrate specificity of tobacco etch virus protease." J. Biol. Chem. 277:50564-50572(2002). PubMed=12377789; DOI=10.1074/jbc.M207224200 [E1] https://viralzone.expasy.org/48?outline=all_by_species [E2] https://www.ebi.ac.uk/merops/cgi-bin/merops.cgi?id=C4 -------------------------------------------------------------------------------- PROSITE is copyrighted by the SIB Swiss Institute of Bioinformatics and distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives (CC BY-NC-ND 4.0) License, see https://prosite.expasy.org/prosite_license.html -------------------------------------------------------------------------------- {END}