Frontiers in plant RNA research in ICAR2023: from lab to innovative agriculture.

The recent growth in global warming, soil contamination, and climate instability have widely disturbed ecosystems, and will have a significant negative impact on the growth of plants that produce grains, fruits and woody biomass. To conquer this difficult situation, we need to understand the molecular bias of plant environmental responses and promote development of new technologies for sustainable maintenance of crop production. Accumulated molecular biological data have highlighted the importance of RNA-based mechanisms for plant stress responses.

Highly ABA-Induced 1 (HAI1)-Interacting protein HIN1 and drought acclimation-enhanced splicing efficiency at intron retention sites.

The Highly ABA-Induced 1 (HAI1) protein phosphatase is a central component of drought-related signaling. A screen for HAI1-interacting proteins identified HAI1-Interactor 1 (HIN1), a nuclear protein of unknown function which could be dephosphorylated by HAI1 in vitro. HIN1 colocalization and interaction with serine-arginine rich (SR) splicing factors and appearance of nuclear speckle-localized HIN1 during low water potential (ψ) stress suggested a pre-mRNA splicing-related function.

Phosphoproteomics of Highly ABA-Induced1 identifies AT-Hook-Like10 phosphorylation required for stress growth regulation.

The clade A protein phosphatase 2C Highly ABA-Induced 1 (HAI1) plays an important role in stress signaling, yet little information is available on HAI1-regulated phosphoproteins. Quantitative phosphoproteomics identified phosphopeptides of increased abundance in in unstressed plants and in plants exposed to low-water potential (drought) stress. The identity and localization of the phosphoproteins as well as enrichment of specific phosphorylation motifs indicated that these phosphorylation sites may be regulated directly by HAI1 or by HAI1-regulated kinases including mitogen-activated protein kinases, sucrose non-fermenting-related kinase 2, or casein kinases.

Epigenetics and RNA Processing: Connections to Drought, Salt, and ABA?

There have been great research advances in epigenetics, RNA splicing, and mRNA processing over recent years. In parallel, there have been many advances in abiotic stress and Abscisic Acid (ABA) signaling. Here we overview studies that have examined stress-induced changes in the epigenome and RNA processing as well as cases where disrupting these processes changes the plant response to abiotic stress.