Biology subjects

Chaturvedi, D.

Publications and source records attributed to Chaturvedi, D..

4 recordsLinked to original sources

bioRxiv2023

Insecticidal Effects of Datura Species against Major Agricultural Pests

Insecticides derived from plants provide environmentally friendly and sustainable options as alternatives to synthetic chemicals. This investigation delves into the insecticidal capabilities of two distinct Datura species, namely, Datura alba and Datura stramonium, in combatting significant pests such as Spodoptera litura, Bemesia tabaci, and Callosobruchus maculatus. Datura plants have a well-documented history of medicinal use and are recognized for their abundant Tropane alkaloid content, which acts as an innate defense mechanism against pests. Hence, the current investigation involved the extraction of chemical compounds from the leaves, flowers, seeds, and roots of both Datura stramonium and Datura alba. Subsequently, these extracts were assessed for efficacy using Spodoptera litura larvae, Bemesia tabaci, and Callosobruchus maculatus in bioassays. The larvicidal experiments encompassed a range of concentrations (3%, 5%, 10%), with larval mortality being documented at multiple time intervals: 6, 12, 24, 48, and 72 hours. The findings from our investigation uncover the notable insecticidal attributes of root, leaf, flower, and seed extracts from both Datura alba and Datura stramonium against these larvae. These extracts demonstrated distinct mortality rates at various concentrations and exposure durations. This comprehensive analysis imparts crucial knowledge regarding the insecticidal qualities of Datura species and their prospective contributions to sustainable pest control practices. The observed effectiveness of these plant extracts against a spectrum of significant pests hints at their potential as ecological alternatives within integrated pest management strategies.

plant biology↗

bioRxiv2022

Structured and disordered regions of Ataxin-2 contribute differently to the specificity and efficiency of mRNP granule formation.

Ataxin-2 (ATXN2) is a gene implicated in spinocerebellar ataxia type II (SCA2), amyotrophic lateral sclerosis (ALS) and Parkinsonism. The encoded protein is a therapeutic target for ALS and related conditions. ATXN2 (or Atx2 in insects) can function in translational activation, translational repression, mRNA stability and in the assembly of mRNP-granules, a process mediated by intrinsically disordered regions (IDRs). Previous work has shown that the LSm (Like-Sm) domain of Atx2, which can help stimulate mRNA translation, antagonizes mRNP-granule assembly. Here we advance these findings through a series of experiments on Drosophila and human Ataxin-2 proteins. Results of Targets of RNA-Binding Proteins Identified by Editing (TRIBE), co-localization and immunoprecipitation experiments indicate that a polyA-binding protein (PABP) interacting, PAM2 motif of Ataxin-2 may be a major determinant of the mRNA and protein content of Ataxin-2 mRNP granules. Transgenic experiments in Drosophila indicate that while the Atx2-LSm domain may protect against neurodegeneration, structured PAM2- and unstructured IDR- interactions both support Atx2-induced cytotoxicity. Taken together, the data lead to a proposal for how Ataxin-2 interactions are remodelled during translational control and how structured and non-structured interactions contribute differently to the specificity and efficiency of RNP granule condensation as well as to neurodegeneration.

neuroscience↗

bioRxiv2020

Heterogeneous distribution of mRNAs within flight muscle fibers, and implications for function

Muscle heterogeneity has been explored in terms of fiber-type distribution, structural organisation, and differences at their junctions with neurons and tendons. We amplify on such observation to additionally suggest that muscle syncytia have nonuniform protein requirements along their length, deployed for developmental and functional uses. An exploration of regionalized proteins or their mRNA across muscle syncytia has not been done. We investigated mRNA localization in regions of Drosophila melanogaster dorsal longitudinal muscle (DLM) syncytia over their entire transcriptome. Dissection of muscle regions, their RNA-seq and stringent Differential Gene Expression analysis indeed reveals statistically significant regionalization of nearly a hundred mRNA over the length of DLMs. Functions of over half of these genes require experimental verification. A preponderance of mRNA coding for catabolic and proteolytic enzymes is conspicuous among transcripts enriched in the posterior of DLMs. Our findings provide a foundation for exploring molecular processes that contribute to syncytial maturation and muscle homeostasis in a spatially non-homogenous manner.

developmental biology↗

bioRxiv2019

Adult Drosophila Muscle Morphometry through MicroCT reveals dynamics during aging

Indirect Flight Muscles (IFMs) in adult Drosophila have served as a valuable model for studying muscle development. In terms of function, they provide the key power stroke in adult insect flight. Variability in their architecture including of fiber numbers, shape and arrangement may provide insightful clues into adult muscle function. Conventional histological preparations in imaging techniques severely limit exact morphometric analysis of flight muscles, thereby impeding causal or correlative studies between muscle morphology and function. In this study we employ MicroCT scanning on a tissue preparation that retains muscle morphology under homeostatic conditions. We use this method to deliver precise measurements of a subset of IFMs, the Direct Longitudinal Muscles (DLMs) size and shape, in male and female Drosophila and changes therein, with age. Our findings reveal several unexpected characteristics of muscle fibers. We also demonstrate application to other insect species making it a valuable tool for histological analysis of insect biodiversity.\n\nSignificance StatementAdult Drosophila muscles serve as models of homeostatic muscles. Accurate analysis of their form and function is key to understanding affects of genetic and physiological states on them. Recording adult muscle shape and volume has so far depended on protocols that inevitably distort tissue. Here, we use a MicroCT scanning based method that delivers changes in shape, size and organization between males and females, with time. This method is a significant step forward in recording muscle structure in situ with applications across species.

developmental biology↗