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Mysore, K.

Publications and source records attributed to Mysore, K..

5 recordsLinked to original sources

Ribosome Processing Factor-2 Interacts with RPL10A to Regulate Selective Translation during Plant Immunity and Drought Stress

Processing of ribosomal RNA (rRNA) is essential for ribosome biogenesis, translation, plant development, and stress adaptation. Ribosome processing factor-2 (RPF2), which plays a role in the later stages of rRNA maturation, interacts with ribosomal protein L10A (RPL10A). RPF2 overexpression in Arabidopsis and Nicotiana benthamiana showed enhanced plant growth and trichome development due to increased gibberellic acid (GA) levels. Conversely, RPF2-silenced and mutant plants had a dwarf phenotype, reduced stomatal apertures, and decreased glucosinolate accumulation. RPF2 silenced and mutant plants also showed compromised nonhost disease resistance, whereas RPF2 overexpression lines exhibited enhanced disease resistance to both host and nonhost pathogens. RPL10A and RPF2 overexpression lines were sensitive to abscisic acid (ABA) and tolerant to drought, which is attributed to their unique roles in translation regulation. Despite having larger stomatal apertures, RPF2 overexpression plants displayed low pathogen multiplication rates and reduced water loss, indicating independent resistance mechanisms associated with ribosomal functions in translation regulation. Although both RPL10A and RPF2 proteins interact with each other and are involved in translation regulation, proteomic analysis suggests that they regulate the translation of distinct sets of genes during pathogen or drought stress. These findings indicate that RPF2 and RPL10A play independent roles in the regulation of unique protein translation.

plant biology↗

Development of an eco-friendly RNAi yeast attractive targeted sugar bait that silences the Shaker gene in spotted-wing drosophila, Drosophila suzukii

BackgroundDrosophila suzukii, or spotted-wing drosophila (SWD), (Diptera: Drosophilidae), are invasive vinegar flies of East Asian origin that have wreaked havoc on the small fruit and berry industry. In locations where SWD are well established, weekly chemical insecticide applications are necessary, resulting in increased economic costs, unwanted environmental impacts ensuing from loss of non-targeted organisms, and the eventual emergence of populations that are resistant to these insecticides. It is therefore critical that new classes of biorational pesticides and cost-effective technologies for controlling SWD are identified. ResultsHere, we used the attractive properties of Saccharomyces cerevisiae, bakers yeast, which was designed to express an RNA interference (RNAi) pesticide that specifically targets the SWD Shaker (Sh) gene, to lure and kill flies that feed on the yeast, which was delivered in a feeder as a component of an attractive targeted sugar bait (ATSB). The yeast, which was heat killed prior to preparation of the ATSB, silenced the Sh gene, resulting in severe neural defects and 96{+/-}9% fly mortality in laboratory trials. The RNAi yeast was successfully fed to the flies in an easily assembled soda bottle feeder that continuously rewetted the yeast with soda, which lured and killed the flies in simulated field trials. Despite this toxicity observed in SWD, consumption of the yeast had no impact on the survival of other dipteran insects. ConclusionThis promising ATSB technology, which was prepared with a new class of RNAi yeast insecticides, could one day be an effective component in integrated SWD control programs.

genetics↗

Light sensitive short hypocotyl (LSH) confer symbiotic nodule identity in the legume Medicago truncatula

Legumes grow specialized root nodules that are distinct from lateral roots in morphology and function, with nodules intracellularly hosting beneficial nitrogen-fixing bacteria that provide the plant with a nitrogen source. We have previously shown that a lateral root-like program underpins nodule initiation, but there must be additional developmental programs that confer nodule identity. Here, we show that two members of the LIGHT SENSITIVE SHORT HYPOCOTYL (LSH) transcription factor family, predominantly known to define organ boundaries and meristem complexity in the shoot, function as regulators of nodule organ identity. LSH1/LSH2 function upstream of and together with the known nodule regulators Nuclear Factor Y-A1 and NODULE ROOT1/2. The principal outcome of LSH1/LSH2 function is the production of cells able to accommodate nitrogen-fixing bacteria, the unique nodule feature. We conclude that the coordinate recruitment of a pre-existing primordium identity program, in parallel to a root initiation program, underpins the divergence between lateral roots and nodules.

plant biology↗

Medicago truncatula Yellow Stripe1-Like3 gene is involved in symbiotic nitrogen fixation

Symbiotic nitrogen fixation carried out in legume root nodules requires transition metals. These nutrients are delivered by the host plant to the endosymbiotic nitrogen-fixing bacteria living with the nodule cells, a process in which vascular transport is essential. As occurs in root-to-shoot transport, members of the Yellow Stripe-Like (YSL) family of metal transporters should also be required for root-to-nodule metal delivery. The genome of the model legume Medicago truncatula encodes for eight YSL proteins, four of them with a high degree of similarity to Arabidopsis thaliana YSLs involved in long-distance metal trafficking. Among them, MtYSL3 is a plasma membrane protein expressed by vascular cells in roots and nodules, and by cortical nodule cells. Reducing expression levels of this gene had no major effect on plant physiology when assimilable nitrogen was provided in the nutrient solution. However, nodule functioning was severely impaired, with a significant reduction of nitrogen fixation capabilities. Further, iron and zinc accumulation and distribution changed. Iron was retained in the apical region of the nodule, while zinc became strongly accumulated in the nodule veins in the ysl3 mutant. These data suggest a role of MtYSL3 in vascular delivery of iron and zinc to symbiotic nitrogen fixation. HighlightMedicago truncatula YSL3 transporter is required for optimal nitrogen fixation in root nodules, mediating iron and zinc distribution in these organs.

plant biology↗

Medicago truncatula MOT1.3 is a plasma membrane molybdenum transporter required for nitrogenase activity in root nodules

O_LIMolybdenum, as a component of the iron-molybdenum cofactor of nitrogenase, is essential for symbiotic nitrogen fixation. This nutrient has to be provided by the host plant through molybdate transporters.\nC_LIO_LIMembers of the molybdate transporters family MOT1 were identified in the model legume Medicago truncatula and their expression in nodules determined. Yeast toxicity assays, confocal microscopy, and phenotypical characterization of a Tnt1 insertional mutant line were carried out in the one M. truncatula MOT1 family member expressed specifically in nodules.\nC_LIO_LIAmong the five MOT1 members present in M. truncatula genome, MtMOT1.3 is the only one uniquely expressed in nodules. MtMOT1.3 shows molybdate transport capabilities when expressed in yeast. Immunolocalization studies revealed that MtMOT1.3 is located in the plasma membrane of nodule cells. A mot1.3-1 knockout mutant showed an impaired growth concomitant with a reduction in nitrogenase activity. This phenotype was rescued by increasing molybdate concentrations in the nutritive solution, or upon addition of an assimilable nitrogen source. Furthermore, mot1.3-1 plants transformed with a functional copy of MtMOT1.3 showed a wild type-like phenotype.\nC_LIO_LIThese data are consistent with a model in which MtMOT1.3 would be responsible for introducing molybdate into nodule cells, which will be later used to synthesize functional nitrogenase.\nC_LI

plant biology↗