Mitochondrial functions in plant immunity

et al. 2023

BMC Plant Biol

Background Mitochondria are organelles within eukaryotic cells that are central to the metabolic processes of cellular respiration and ATP production. However, the evolution of mitochondrial genomes (mitogenomes) in plants is virtually unknown compared to animal mitogenomes or plant plastids, due to complex structural variation and long stretches of repetitive DNA making accurate genome assembly more challenging. Comparing the structural and sequence differences of organellar genomes within and between sorghum species is an essential step in understanding evolutionary processes such as organellar sequence transfer to the nuclear genome as well as improving agronomic traits in sorghum related to cellular metabolism. Results Here, we assembled seven sorghum mitochondrial and plastid genomes and resolved reticulated mitogenome structures with multilinked relationships that could be grouped into three structural conformations that differ in the content of repeats and genes by contig. The grouping of these mitogenome structural types reflects the two domestication events for sorghum in east and west Africa. Conclusions We report seven mitogenomes of sorghum from different cultivars and wild sources. The assembly method used here will be helpful in resolving complex genomic structures in other plant species. Our findings give new insights into the structure of sorghum mitogenomes that provides an important foundation for future research into the improvement of sorghum traits related to cellular respiration, cytonuclear incompatibly, and disease resistance.

Section: Introductionmentioning

confidence: 99%

Variation in mitogenome structural conformation in wild and cultivated lineages of sorghum corresponds with domestication history and plastome evolution

Zhang

et al. 2023

BMC Plant Biol

“…Most recently, mitochondria are found as the main replication sites of SCMV ( Xie et al., 2021 ). Considering that mitochondria function in multiple plant immunity pathways, including hormone-mediated immunity, programmed cell death, pathogen-associated molecular pattern-triggered immunity, effector-triggered immunity, and defense signal transduction, as well as the connection of mitochondria with other organelles in plant immunity ( Wang et al., 2022 ), it will be interesting for further research to determine whether lactate has an impact on mitochondrion-mediated immune responses in plants.…”

Section: Discussionmentioning

confidence: 99%

Sugarcane mosaic virus orchestrates the lactate fermentation pathway to support its successful infection

Jiang

et al. 2023

Front. Plant Sci.

Viruses often establish their own infection by altering host metabolism. How viruses co-opt plant metabolism to support their successful infection remains an open question. Here, we used untargeted metabolomics to reveal that lactate accumulates immediately before and after robust sugarcane mosaic virus (SCMV) infection. Induction of lactate-involved anaerobic glycolysis is beneficial to SCMV infection. The enzyme activity and transcriptional levels of lactate dehydrogenase (LDH) were up-regulated by SCMV infection, and LDH is essential for robust SCMV infection. Moreover, LDH relocates in viral replicase complexes (VRCs) by interacting with SCMV-encoded 6K2 protein, a key protein responsible for inducing VRCs. Additionally, lactate could promote SCMV infection by suppressing plant defense responses. Taken together, we have revealed a viral strategy to manipulate host metabolism to support replication compartment but also depress the defense response during the process of infection.

“…For example, upon pathogen attack, plant mitochondria can produce mitochondrial ROS, reactive nitrogen species, etc. that ultimately trigger programmed cell death and defense pathways (Wang et al., 2022).…”

Section: Discussionmentioning

confidence: 99%

Cotton peroxisome‐localized lysophospholipase counteracts the toxic effects of Verticillium dahliaeNLP1 and confers wilt resistance

Song

et al. 2023

The Plant Journal

SUMMARY Plasma membrane represents a critical battleground between plants and attacking microbes. Necrosis‐and‐ethylene‐inducing peptide 1 (Nep1)‐like proteins (NLPs), cytolytic toxins produced by some bacterial, fungal and oomycete species, are able to target on lipid membranes by binding eudicot plant‐specific sphingolipids (glycosylinositol phosphorylceramide) and form transient small pores, causing membrane leakage and subsequent cell death. NLP‐producing phytopathogens are a big threat to agriculture worldwide. However, whether there are R proteins/enzymes that counteract the toxicity of NLPs in plants remains largely unknown. Here we show that cotton produces a peroxisome‐localized enzyme lysophospholipase, GhLPL2. Upon Verticillium dahliae attack, GhLPL2 accumulates on the membrane and binds to V. dahliae secreted NLP, VdNLP1, to block its contribution to virulence. A higher level of lysophospholipase in cells is required to neutralize VdNLP1 toxicity and induce immunity‐related genes expression, meanwhile maintaining normal growth of cotton plants, revealing the role of GhLPL2 protein in balancing resistance to V. dahliae and growth. Intriguingly, GhLPL2 silencing cotton plants also display high resistance to V. dahliae, but show severe dwarfing phenotype and developmental defects, suggesting GhLPL2 is an essential gene in cotton. GhLPL2 silencing results in lysophosphatidylinositol over‐accumulation and decreased glycometabolism, leading to a lack of carbon sources required for plants and pathogens to survive. Furthermore, lysophospholipases from several other crops also interact with VdNLP1, implying that blocking NLP virulence by lysophospholipase may be a common strategy in plants. Our work demonstrates that overexpressing lysophospholipase encoding genes have great potential for breeding crops with high resistance against NLP‐producing microbial pathogens.