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Asian agriculture sector contributes about 44% of greenhouse gas (GHG) emission. Predominantly paddy rice cultivation couples with indiscriminate use of agrochemicals, burning of fossil fuels in farm machinery majorly causes GHG emissions from farmlands in Asia. Presently, Asian soils have 25% cropland soil organic carbon (SOC) content but with moderately to highly vulnerability towards land degradation. To make up the soil carbon losses which has occurred due to continuous cultivation and tillage, it is recommended to adopt suitable carbon management practices to sequester carbon in soil through their physio-chemical protection. Conservation agriculture (CA), cover crop, crop diversification, integrated nutrient management (INM) and balanced fertilisation promotes better soil structure formation, stabilisation of aggregate associated carbon, microbial polymerisation of organic matter as well as a better root architecture. Carbon management practices not only improve soil fertility but also supports improved grain and straw yield. More the yield more biomass addition occurs to the soil. Soil carbon sequestration may not be the only panacea of climate change related issues, but is certainly a way forward to enriched soil fertility, improved agronomic production as well as adaptive- mitigation for offsetting anthropogenic GHG emission.

Pontin and Reptin are essential eukaryotic AAA+ ATPases that work together in several multiprotein complexes, contributing to chromatin remodeling and TARGET OF RAPAMCYIN (TOR) kinase complex assembly, among other functions. Null alleles of pontin or reptin are gametophyte lethal in plants, which has hindered studies of their crucial roles in plant biology. Here, we used virus-induced gene silencing (VIGS) to interrogate the functions of Pontin and Reptin in plant growth and physiology, focusing on Nicotiana benthamiana, a model species for the agriculturally significant Solanaceae family. Silencing either Pontin or Reptin caused pleiotropic developmental and physiological reprogramming, including aberrant leaf shape, reduced apical growth, delayed flowering, increased branching, chlorosis, and decreased spread of the RNA viruses Tobacco mosaic virus (TMV) and Potato virus X (PVX). To dissect these pleiotropic phenotypes, we took a comparative approach and silenced expression of key genes that encode subunits of each of the major Pontin/Reptin-associated chromatin remodeling or TOR complexes (INO80, SWR-C/PIE1, TIP60, TOR, and TELO2). We found that many of the pontin/reptin phenotypes could be attributed specifically to disruption of one of these complexes, with tip60 and tor knockdown plants each phenocopying a large subset of pontin/reptin phenotypes. We conclude that Pontin/Reptin complexes are crucial for proper plant development, physiology, and stress responses, highlighting the multifaceted roles these conserved enzymes have evolved in eukaryotic cells.

The exploitation of nature for decades due to several anthropogenic activities has changed the climatic conditions worldwide. The environment has been polluted with an increase of greenhouse gases. The major consequences are global warming, cyclone, an increase in sea level, etc. It has a clear negative impact on the natural environment including aquatic ones. As a result, production of fish in the aquaculture system and marine system is greatly affected. Marine ecosystems like coral reefs are also destroyed. Decreased fish production has also affected the livelihood and economic condition of the fish farmers. So, corrective measures should be taken to reduce the climate changes for minimizing its effects on fish production. Using more eco-friendly substances, planting more trees, and preserving our nature are some steps to be taken. Awareness should also be generated among the common people.

Salicylic acid (SA) and reactive oxygen species (ROS) are known to be key modulators of plant defense. However, mechanisms of molecular signal perception and appropriate physiological responses to SA and ROS during biotic or abiotic stress are poorly understood. Here we report characterization of SMALL DEFENSE-ASSOCIATED PROTEIN 1 (SDA1), which modulates defense against bacterial pathogens and tolerance to oxidative stress. sda1 mutants are compromised in defense gene expression, SA accumulation, and defense against bacterial pathogens. External application of SA rescues compromised defense in sda1 mutants. sda1 mutants are also compromised in tolerance to ROS-generating chemicals. Overexpression of SDA1 leads to enhanced resistance against bacterial pathogens and tolerance to oxidative stress. These results suggest that SDA1 regulates plant immunity via the SA-mediated defense pathway and tolerance to oxidative stress. SDA1 encodes a novel small plant-specific protein containing a highly conserved seven amino acid (S/G)WA(D/E)QWD domain at the N-terminus that is critical for SDA1 function in pathogen defense and tolerance to oxidative stress. Taken together, our studies suggest that SDA1 plays a critical role in modulating both biotic and abiotic stresses in Arabidopsis (Arabidopsis thaliana) and appears to be a plant-specific stress responsive protein.

The coordinated redistribution of sugars from mature “source” leaves to developing “sink” leaves requires tight regulation of sugar transport between cells via plasmodesmata (PD). Although fundamental to plant physiology, the mechanisms that control PD transport and thereby support development of new leaves have remained elusive. From a forward genetic screen for altered PD transport, we discovered that the conserved eukaryotic glucose-TOR (TARGET OF RAPAMYCIN) metabolic signaling network restricts PD transport in leaves. Genetic approaches and chemical or physiological treatments to either promote or disrupt TOR activity demonstrate that glucose-activated TOR decreases PD transport in leaves. We further found that TOR is significantly more active in mature leaves photosynthesizing excess sugars than in young, growing leaves, and that this increase in TOR activity correlates with decreased rates of PD transport. We conclude that leaf cells regulate PD trafficking in response to changing carbohydrate availability monitored by the TOR pathway.

Antibody-drug conjugates (ADCs) combine the high specificity of antibodies with cytotoxic payloads. However, the present strategies for the synthesis of ADCs either yield unstable or heterogeneous products or involve complex processes. Here, we report a computational approach that leverages molecular docking and molecular dynamics simulations to design ADCs that self-assemble through the non-covalent binding of the antibody to a payload that we designed to act as an affinity ligand for specific conserved amino acid residues in the antibody. This method does not require modifications to the antibody structure and yields homogenous ADCs that form in less than 8 min. We show that two conjugates, which consist of hydrophilic and hydrophobic payloads conjugated to two different antibodies, retain the structure and binding properties of the antibody and its biological specificity, are stable in plasma and improve anti-tumour efficacy in mice with non-small cell lung tumour xenografts. The relative simplicity of the approach may facilitate the production of ADCs for the targeted delivery of cytotoxic payloads.

The alternative sigma factor RpoN is a unique regulator found among bacteria. It controls numerous processes that range from basic metabolism to more complex functions such as motility and nitrogen fixation. Our current understanding of RpoN function is largely derived from studies on prototypical bacteria such as Escherichia coli. Bacillus subtilis and Pseudomonas putida. Although the extent and necessity of RpoN-dependent functions differ radically between these model organisms, each bacterium depends on a single chromosomal rpoN gene to meet the cellular demands of RpoN regulation. The bacterium Ralstonia solanacearum is often recognized for being the causative agent of wilt disease in crops, including banana, peanut and potato. However, this plant pathogen is also one of the few bacterial species whose genome possesses dual rpoN genes. To determine if the rpoN genes in this bacterium are genetically redundant and interchangeable, we constructed and characterized ΔrpoN1, ΔrpoN2 and ΔrpoN1 ΔrpoN2 mutants of R. solanacearum GMI1000. It was found that growth on a small range of metabolites, including dicarboxylates, ethanol, nitrate, ornithine, proline and xanthine, were dependent on only the rpoN1 gene. Furthermore, the rpoN1 gene was required for wilt disease on tomato whereas rpoN2 had no observable role in virulence or metabolism in R. solanacearum GMI1000. Interestingly, plasmid-based expression of rpoN2 did not fully rescue the metabolic deficiencies of the ΔrpoN1 mutants; full recovery was specific to rpoN1. In comparison, only rpoN2 was able to genetically complement a ΔrpoN E. coli mutant. These results demonstrate that the RpoN1 and RpoN2 proteins are not functionally equivalent or interchangeable in R. solanacearum GMI1000.

Cdk5/p25 has emerged as a principle therapeutic target for numerous acute and chronic neurodegenerative diseases, including Alzheimer's disease. A structure-activity relationship study of 2,4-diaminothiazole inhibitors revealed that increased Cdk5/p25 inhibitory activity could be accomplished by incorporating pyridines on the 2-amino group and addition of substituents to the 2- or 3-position of the phenyl ketone moiety. Interpretation of the SAR results for many of the analogs was aided through in silico docking with Cdk5/p25 and calculating protein hydrations sites using WaterMap. Finally, improved in vitro mouse microsomal stability was also achieved.