Biology subjects

Rodriguez, P. L.

Publications and source records attributed to Rodriguez, P. L..

4 recordsLinked to original sources

bioRxiv2023

ABI5-FLZ13 Module Transcriptionally Represses Growth-related Genes to Delay Seed Germination in Response to ABA

The bZIP transcription factor ABSCISIC ACID INSENSITIVE5 (ABI5) is a master regulator determining seed germination and postgerminative growth in response to abscisic acid (ABA), but the detailed molecular mechanism underlying the repression function of ABI5 in plant growth remains to be characterized. In this study, we used proximity labeling (PL) to map the neighboring proteome of ABI5 and identified FCS-LIKE ZINC FINGER PROTEIN 13 (FLZ13) as an up-to-now unknown ABI5-interacting partner. Phenotypic analysis of flz13 mutants and FLZ13-overexpressing lines demonstrated that FLZ13 acts as a positive regulator of ABA signaling. Interestingly, transcriptomic analysis showed that ABI5 and FLZ13 co-downregulate the expression of ABA-repressed and growth-related genes involved in chlorophyll biosynthesis, photosynthesis and cell wall organization, thereby repressing seed germination and seedling establishment in response to ABA. Further genetic analysis proved that FLZ13 works synergistically with ABI5 to regulate seed germination. Collectively, our study reveals a previously uncharacterized transcriptional regulatory mechanism regarding ABA-inhibited seed germination and seedling establishment.

plant biology↗

bioRxiv2021

CAR modulates plasma membrane nano-organization and immune signaling downstream of RALF1-FERONIA ligand-receptor signaling system

O_LIThe receptor-like kinase (RLK) FERONIA (FER) senses peptide ligands in the plasma membrane (PM), modulates plant growth and development, and integrates biotic and abiotic stress signaling for downstream adaptive response. However, the molecular interplay of these diverse processes is largely unknown. C_LIO_LIHere, we show that FER, the receptor of Rapid Alkalinization Factor 1 (RALF1), physically interacts with C2 domain ABA-related (CAR) proteins to control the nano-organization of the PM in Arabidopsis. C_LIO_LIDuring this process, the RALF1-FER pathway upregulates CAR protein translation, and then more CAR proteins are recruited to PM. This acts as a rapid feedforward loop to stabilize PM liquid-ordered phase. FER interacts with and phosphorylates CARs, and reducing their lipid-binding ability, which breaks the feedback regulation CAR activity at latter time point. C_LIO_LISimilar to FER mutant, pentuple car14569 mutants inhibit flg22-induced FLS2-BAK1 immune complex formation, which depends on the integrity of nanodomains. O_LITogether, we propose that the FER-CAR module controls the formation of the PM nano-organization during RALF signaling through a self-contained amplifying loop including both positive and negative feedbacks. C_LI C_LI

plant biology↗

bioRxiv2020

PYL8 ABA receptors of Phoenix dactylifera play a crucial role in response to abiotic stress and are stabilized by ABA

The identification of those prevailing ABA receptors and molecular mechanisms that trigger drought adaptation in crops well adapted to harsh conditions such as date palm (Phoenix dactylifera, Pd) sheds light on plant-environment interactions. We reveal that PdPYL8-like receptors are predominantly expressed under abiotic stress, being Pd27 the most expressed receptor in date palm. Therefore, subfamily I PdPYL8-like receptors have been selected for ABA signaling during abiotic stress response in this crop. Biochemical characterization of PdPYL8-like and PdPYL1-like receptors revealed receptor- and ABA-dependent inhibition of PP2Cs, which triggers activation of the pRD29B-LUC reporter in response to ABA. PdPYLs efficiently abolish PP2C-mediated repression of ABA signaling, but loss of the Trp lock in the seed-specific AHG1-like phosphatase PdPP2C79 markedly impairs its inhibition by ABA receptors. Characterization of Arabidopsis transgenic plants that express PdPYLs shows enhanced ABA signaling in seed, root and guard cells. Specifically, Pd27 overexpressing (OE) plants showed lower ABA content and were more efficient than wild type to lower transpiration at negative soil water potential, leading to enhanced drought tolerance. Finally, PdPYL8-like receptors accumulate after ABA treatment, which suggests that ABA-induced stabilization of these receptors operates in date palm for efficient boosting of ABA signaling in response to abiotic stress. HighlightDate palm response to abiotic stress is triggered through PYL8-like ABA receptors that are stabilized by the hormone, which boosts plant adaptation to drought mediated by ABA.

plant biology↗

bioRxiv2019

The fungal sesquiterpenoid pyrenophoric acid B uses the plant ABA biosynthetic pathway to inhibit seed germination.

HighlightThe fungus Pyrenophora semeniperda produces pyrenophoric acid B, a small molecule that exploits the plant ABA biosynthetic pathway to reduce seed germination, increasing its reproductive success.\n\nAbstractPyrenophoric acid (P-Acid), P-Acid B and P-Acid C are three phytotoxic sesquiterpenoids produced by the ascomycete seed pathogen Pyrenophora semeniperda, a fungus proposed as a mycoherbicide for biocontrol of cheatgrass, an extremely invasive weed. When tested in cheatgrass bioassays these metabolites were able to delay seed germination, with P-Acid B being the most active compound. Here, we have investigated the cross-kingdom activity of P-Acid B and its mode of action and found that it activates the ABA signaling pathway in order to inhibit seedling establishment. P-Acid B inhibits seedling establishment in wild-type Arabidopsis thaliana while several mutants affected in the early perception as well as in downstream ABA signaling components were insensitive to the fungal compound. However, in spite of structural similarities between ABA and P-Acid B, the latter is not able to activate the PYR/PYL family of ABA receptors. Instead, we have found that P-Acid B uses the ABA biosynthesis pathway at the level of alcohol dehydrogenase ABA2 to reduce seedling establishment. We propose that the fungus Pyrenophora semeniperda manipulates plant ABA biosynthesis as a strategy to reduce seed germination, increasing its ability to cause seed mortality and thereby increase its fitness through higher reproductive success.

plant biology↗