Biochemical controls: plant immunity against viruses (Introduction)

by David Turell , Tuesday, August 13, 2024, 21:36 (34 days ago) @ David Turell

Specialized proteins:

https://phys.org/news/2024-08-scientists-reveal-mechanism-immunity-viruses.html

"Arginine methylation is an important post-translational modification involved in transcriptional regulation, RNA processing, DNA damage repair, and immune response. Protein arginine methyltransferases (PRMTs) are the evolutionarily conserved protein family responsible for catalyzing protein arginine methylation.

"Plant PRMTs affect plant development and stress response through transcriptional and post-transcriptional regulation. However, it remains largely unknown whether PRMTs are involved in plant disease resistance.

"Chinese scientists established PRMT6-mediated arginine methylation of viral suppressor RNA silencing (VSR) as a novel mechanism of plant immunity against viruses. Their work, titled "Protein targeting methyltransferase 6 media antiviral immunity in plants," was published in Cell Host & Microbe on Aug. 5.

"The siRNA-mediated antiviral gene silencing plays a key role in plant defense against viruses. VSRs encoded by viruses inhibit antiviral RNA silencing.

"During plant-virus co-evolution, plants have evolved additional countering strategies to target VSR, such as autophagy and nucleotide-binding-leucine-rich repeat (NLR) containing immune receptor-mediated immunity.

"Tomato bush stunt virus (TBSV)-encoded P19 is a well-studied VSR that promotes viral systemic movement by binding to the siRNA duplex.

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"Through bioinformatics analysis, the scientists identified a tomato protein, SlyPRMT6, which is homologous to PRMT6 in humans and Arabidopsis. SlyPRMT6 knockout mutants displayed reduced tomato resistance to TBSV infection while SlyPRMT6 overexpression increased the TBSV resistance. This indicated that SlyPRMT6 plays a role in tomato antiviral responses.

"Two PRMT6 alleles were then identified in the natural tomato population, showing a significant correlation with PRMT6 expression levels and TBSV resistance. This finding suggested that the allele associated with high expression could be valuable for resistance breeding."

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Comment: another study to show that precise proteins exert defined reactions in immune systems.