The Great Game between Plants and Viruses: A Focus on Protein Homeostasis.

Plant viruses are tiny pathogenic obligate parasites that cause significant damage to global crop production. They exploit and manipulate the cellular components of host plants to ensure their own survival. In response, plants activate multiple defense signaling pathways, such as gene silencing and plant hormone signaling, to hinder virus propagation.

Activation of MAPK-mediated immunity by phosphatidic acid in response to positive-strand RNA viruses.

Increasing evidence suggests that mitogen-activated protein kinase (MAPK) cascades play a crucial role in plant defense against viruses. However, the mechanisms that underlie the activation of MAPK cascades in response to viral infection remain unclear. In this study, we discovered that phosphatidic acid (PA) represents a major class of lipids that respond to Potato virus Y (PVY) at an early stage of infection.

Cucurbit Chlorotic Yellows Virus p22 Protein Interacts with Cucumber SKP1LB1 and Its F-Box-Like Motif Is Crucial for Silencing Suppressor Activity.

Plants use RNA silencing as a defense against viruses. In response, viruses encode various RNA silencing suppressors to counteract the antiviral silencing. Here, we identified p22 as a silencing suppressor of cucurbit chlorotic yellows crinivirus and showed that p22 interacts with CsSKP1LB1, a ortholog of S-phase kinase-associated protein 1 (SKP1).

Purification and Characterization of a Secretory Alkaline Metalloprotease with Highly Potent Antiviral Activity from Serratia marcescens Strain S3.

In this study we report a secretory protein that was purified from Serratia marcescens strain S3 isolated from soil from the tobacco rhizosphere. Subsequent mass spectrometry and annotation characterized the protein as secretory alkaline metalloprotease (SAMP). SAMP plays a crucial role in inhibiting Tobacco mosaic virus (TMV).

Complete genome sequence of an alternavirus from the phytopathogenic fungus Fusarium incarnatum.

A novel double-stranded RNA (dsRNA) mycovirus, named "Fusarium incarnatum alternavirus 1" (FiAV1), was found in Fusarium incarnatum strain LY003-07, the causal agent of peony root rot. The complete genome of FiAV1 is composed of three dsRNA segments, dsRNA1 (3548 nt), dsRNA2 (2514 nt), and dsRNA3 (2498 nt), with one open reading frame on each of their positive-sense strands. As found in other viruses of the proposed family Alternaviridae, the positive-sense strand of each genomic dsRNA of FiAV1 has a poly(A) tail and the 5'-terminal nonamer sequence 5'-GGCTGTGTG-3'.

First comprehensive proteome analysis of lysine crotonylation in seedling leaves of Nicotiana tabacum.

Histone crotonylation is a new lysine acylation type of post-translational modification (PTM) enriched at active gene promoters and potential enhancers in yeast and mammalian cells. However, lysine crotonylation in nonhistone proteins and plant cells has not yet been studied. In the present study, we performed a global crotonylation proteome analysis of Nicotiana tabacum (tobacco) using high-resolution LC-MS/MS coupled with highly sensitive immune-affinity purification.