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Patil, G. B.

Publications and source records attributed to Patil, G. B..

4 recordsLinked to original sources

A Grass-Specific Structural Feature of Myosin VIII Regulates Protoxylem Development and Hydraulic Conductance in Sorghum

Sorghum (Sorghum bicolor), a C grass adapted to hot semi-arid environments, depends on reinforced xylem vessels to maintain hydraulic conductance under high evaporative demand. During protoxylem differentiation, coordinated microtubule and actin dynamics guide secondary cell wall (SCW) deposition; however, whether actin-based motors directly regulate vascular architecture and hydraulic performance has remained unknown. Here, we identify HEAT-SENSITIVE 1 (HS1), a previously uncharacterized myosin VIII, as a central regulator of protoxylem integrity and water transport in sorghum. The hs1 mutant exhibited severe leaf scorching under field conditions. The hs1 mutant displayed severe leaf scorching under field conditions, accompanied by pronounced protoxylem defects under controlled environments, including vessel collapse, reduced lumen area, and attenuated lignified SCWs. These structural abnormalities compromised longitudinal hydraulic conductance, diminished whole-plant water use, and rendered expanding leaves unable to meet transpirational demand, resulting in transient water deficit and thermal injury. HS1 encoded a grass-specific myosin VIII with a grass-specific N-terminal extension exhibiting high intrinsic disorder and lineage-specific substitutions in the motor domain. Molecular and single-cell transcriptome analyses positioned HS1 within differentiating protoxylem cells of developing leaves, revealing pronounced temporal and cell-type specificity. Furthermore bulk transcriptome profiling and quantitative lignin measurements indicated that HS1 promoted lignin-associated SCW biosynthesis during protoxylem differentiation, functionally linking actin-based motor activity to wall reinforcement. HS1 encodes a grass-specific myosin VIII distinguished by an extended intrinsically disordered N-terminal region and lineage-specific substitutions within the motor domain, suggesting evolutionary specialization. Consistant with core developmental role, reduced nucleotide diversity at the HS1 locus across diverse sorghum accessions further supported strong evolutionary constraint. Together, these findings established HS1 as the first actin-based motor protein shown to control xylem architecture and hydraulic function in plants.

plant biology↗

Developmental regulators enable rapid and efficient soybean transformation and CRISPR-mediated genome editing

Soybean transformation remains challenging and has not kept pace with the rapid advancement of genetic engineering technologies due to low efficiency, lengthy timelines, and genotype dependency. Here, we developed a streamlined transformation method by leveraging developmental regulators (DRs) to promote de novo shoot regeneration directly from growing soybean plants. By evaluating multiple DR combinations, our results showed that co-expression of WUSCHEL2 (WUS2) and isopentenyltransferase (IPT) achieved higher transformation efficiencies (15.2% to 22.3%) in Williams 82 and Bert varieties than individual DRs without requiring exogenous hormones or selection agents. Moreover, this method produces heritable transgenic events within 9-11 weeks and successfully delivers CRISPR-Cas9 components, generating heritable mutations with 20% efficiency. The temporal transcriptomic and gene regulatory network analyses revealed that WUS2/IPT synergistically modulates stress responses and activates developmental pathways, orchestrating a transition from initial stress adaptation to regenerative programming. Together, our findings demonstrate that this DR-enabled approach significantly enhances soybean transformation efficiency, reduces tissue culture requirements, and offers a promising genome editing platform for soybean improvement.

plant biology↗

Shoot at Site: Advancing in planta transformation, regeneration and gene-editing through a cascade of wounding-mediated developmental regulators

Developing transgenic and/or gene-edited plants largely depends on tedious, lengthy, and costly in vitro regeneration protocols. While plants have remarkable regeneration ability, not all species, genotypes or even explants exhibit the same transformation and regeneration potential under in vitro conditions. To tackle this bottleneck, we have developed a seamless and user-friendly system to induce transgenic and gene-edited de novo meristems via a synthetic cascade comprising a wound-induced regeneration pathway, plant developmental regulators (DRs) and gene-editing reagents. WOUND INDUCED DEDIFFERENTIATION 1 (WIND1) is used as a transcriptional regulator to control the expression of various DR genes through ENHANCER OF SHOOT REGENERATION 1 (ESR1) promoter. This cascade was strategically applied in planta to the non-meristematic internode of N. benthamiana to induce meristematic activity and regenerate de novo shoots with knock-out mutations of the phytoene desaturase (PDS) gene. This synthetic toolkit was further applied successfully to tomato and soybean. This methodology offers a transformative approach to overcome barriers in plant biotechnology, potentially accelerating the generation of transgenic and gene-edited plants without reliance on conventional tissue-culture intermediates.

plant biology↗

Identification of cell-type-specific response to silicon treatment in soybean leaves through single nucleus RNA-sequencing

In agriculture, mineral nutrients uptake and deposition profoundly influence plant development, stress resilience, and productivity. Despite its classification as a non-essential element, silicon (Si) is crucial in plant physiology, particularly in defense response and stress mitigation. While genetic and molecular mechanisms of Si uptake and transport are well-studied in monocots, particularly rice, its role in dicot species, such as soybean, remains unclear at the cellular and molecular levels. Traditional bulk transcriptomics methods lack the resolution to uncover cellular heterogeneity. Here, we present a study by utilizing single-nucleus RNA sequencing (snRNA-seq) to dissect cellular responses to Si accumulation in soybean leaves. Our analysis revealed distinct cellular populations, including a novel Si-induced cell cluster within vascular cells, suggesting a specific mechanism of Si distribution. Si treatment induced the expression of defense-related genes, particularly enriched in vascular cells, highlighting their specialized role in activating plant defense mechanisms. Moreover, Si modulated the expression of genes involved in RNA silencing, phytoalexin biosynthesis, and immune receptor signaling, suggesting a mechanism of transcriptional priming of genes involved in defense responses. We further investigated putative Si transporters, revealing differential expression patterns in response to Si treatment, suggesting presence of active and gradient-based transport mechanisms. Our findings shed light on the vital biotic stress regulatory networks governed by Si treatment in soybean leaves, paving potential strategies for enhancing stress tolerance and agronomic performance in crops.

plant biology↗