Dataset Information

The Hypervariable Amino-Terminus of P1 Protease Modulates Potyviral Replication and Host Defense Responses

ABSTRACT: The replication of many RNA viruses involves the translation of polyproteins, whose processing by endopeptidases is a critical step for the release of functional subunits. P1 is the first protease encoded in plant potyvirus genomes; once activated by an as-yet-unknown host factor, it acts in cis on its own C-terminal end, hydrolyzing the P1-HCPro junction. Earlier research suggests that P1 cooperates with HCPro to inhibit host RNA silencing defenses. Using Plum pox virus as a model, we show that although P1 does not have a major direct role in RNA silencing suppression, it can indeed modulate HCPro function by its self-cleavage activity. To study P1 protease regulation, we used bioinformatic analysis and in vitro activity experiments to map the core C-terminal catalytic domain. We present evidence that the hypervariable region that precedes the protease domain is predicted as intrinsically disordered, and that it behaves as a negative regulator of P1 proteolytic activity in in vitro cleavage assays. In viral infections, removal of the P1 protease antagonistic regulator is associated with greater symptom severity, induction of salicylate-dependent pathogenesis-related proteins, and reduced viral loads. We suggest that fine modulation of a viral protease activity has evolved to keep viral amplification below host-detrimental levels, and thus to maintain higher long-term replicative capacity.

INSTRUMENT(S): TripleTOF 5600

ORGANISM(S): Nicotiana Benthamiana

TISSUE(S): Leaf

SUBMITTER: Sergio Ciordia

LAB HEAD: Juan Antonio García

PROVIDER: PXD017769 | Pride | 2020-08-11

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	01_Fabio_iTRAQ_Rep1_14dic13.mgf	Mgf
	01_Fabio_iTRAQ_Rep1_14dic13.pride.mgf.gz	Mgf
	03_Fabio_iTRAQ_Rep2_14dic13.mgf	Mgf
	03_Fabio_iTRAQ_Rep2_14dic13.pride.mgf.gz	Mgf
	05_Fabio_iTRAQ_Rep3_14dic13.mgf	Mgf

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Publications

The hypervariable amino-terminus of P1 protease modulates potyviral replication and host defense responses.

Pasin Fabio F Simón-Mateo Carmen C García Juan Antonio JA

PLoS pathogens 20140306 3

The replication of many RNA viruses involves the translation of polyproteins, whose processing by endopeptidases is a critical step for the release of functional subunits. P1 is the first protease encoded in plant potyvirus genomes; once activated by an as-yet-unknown host factor, it acts in cis on its own C-terminal end, hydrolyzing the P1-HCPro junction. Earlier research suggests that P1 cooperates with HCPro to inhibit host RNA silencing defenses. Using Plum pox virus as a model, we show that ...[more]

PMID: 24603811

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