Abhishek Sadhu

In the present study, a set of 36 Indian mustard genotypes were evaluated in three replications for twelve agro morphological traits. D2 analysis was done to study the diversity pattern which enabled the grouping of genotypes into 11 clusters. Cluster I was the largest (D2=7.53) comprising of 20 genotypes followed by cluster II (D2=7.20) of 7 genotypes, while other 9 clusters contained one genotype each. Estimates of average inter cluster distance revealed that clusters IX and XI were most divergent (D2=118.49) followed by clusters V and XI (D2=88.48). Hence, crossing between genotypes Pusa Agrani × Rohini (cluster IX × cluster XI); PM-28 × Rohini (cluster V × cluster XI) may yields a considerable amount of heterosis in F1 generation. Days to maturity (31.9 %) had the highest contribution, followed by seed yield per plant (25.4 %), days to 50% flowering (13.33 %), beak length (7.30 %) and 1000 seed weight (6.67 %) towards the observed genetic diversity. Selection for divergent parents based on concerned traits could enhance the development of transgressive segregants with increased vigor in Indian mustard

Changes in the transcriptome are critical in shaping the structural plasticity of neurons, which underpins learning and long-term memory storage. Here, we explored the effect of two opposing, plasticity-associated pathways—cAMP second-messenger signaling and metabotropic glutamate receptor (mGluR1 and mGluR5) signaling—on the transcriptome in hippocampal neurons and how these pathways operate in distinct and coordinated manners to induce structural changes. Integration of transcriptome data and molecular pathway analysis identified central “hub” genes that were rapidly induced by cAMP and/or mGluR1/5 in hippocampal neurons. These included the long noncoding RNA (lncRNA) Gas5, whose expression was induced specifically by cAMP and which was targeted to dendrites by the kinesin motor protein KIF1A. In the dendrites, Gas5 interacted with various proteins and coding and noncoding RNAs associated with synaptic function and plasticity, and these interactions were altered by cAMP signaling. Gas5 interacted with the microRNA miR-26a-5p and sequestered it from several of its mRNA targets associated with neuronal function and whose translation was induced by cAMP. Gas5 was critical for excitatory synaptic transmission induced by cAMP but not those induced by mGluR1/5. Furthermore, Gas5 deficiency impaired dendritic branching and synapse morphology, and Gas5 abundance was decreased in the hippocampus of a mouse model of Alzheimer’s disease. Together, these findings provide insight into the transcriptional networks involved in synaptic plasticity and a lncRNA interactome that mediates dendritically localized regulation of excitatory synaptic transmission and neuronal architecture.

Synergistic interaction of nitric oxide (NO) and reactive oxygen species (ROS) is essential to initiate cell death mechanisms in plants. Though autophagy is salient in either restricting or promoting hypersensitivity response (HR)-related cell death, the crosstalk between the reactive intermediates and autophagy during hypersensitivity response is paradoxical. In this investigation, the consequences of Alternaria alternata toxin (AaT) in tobacco BY-2 cells were examined. At 3 h, AaT perturbed intracellular ROS homeostasis, altered antioxidant enzyme activities, triggered mitochondrial depolarization and induced autophagy. Suppression of autophagy by 3-Methyladenine caused a decline in cell viability in AaT treated cells, which indicated the vital role of autophagy in cell survival. After 24 h, AaT facilitated Ca²⁺ influx with an accumulation of reactive oxidant intermediates and NO, to manifest necrotic cell death. Inhibition of NO accumulation by 2-(4-Carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) decreased the level of necrotic cell death, and induced autophagy, which suggests NO accumulation represses autophagy and facilitates necrotic cell death at 24 h. Application of N-acetyl-L-cysteine at 3 h, confirmed ROS to be the key initiator of autophagy, and together with cPTIO for 24 h, revealed the combined effects of NO and ROS is required for necrotic HR cell death.

Background and Aims Cytological parameters such as chromosome numbers and genome sizes of plants are used routinely for studying evolutionary aspects of polyploid plants. Members of Zingiberaceae show a wide range of inter- and intrageneric variation in their reproductive habits and ploidy levels. Conventional cytological study in this group of plants is severely hampered by the presence of diverse secondary metabolites, which also affect their genome size estimation using flow cytometry. None of the several nuclei isolation buffers used in flow cytometry could be used very successfully for members of Zingiberaceae to isolate good quality nuclei from both shoot and root tissues.