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Rani, J.

Publications and source records attributed to Rani, J..

8 recordsLinked to original sources

Male Age and Sexual Maturity: Lipopolysaccharide-induced tumor necrosis factor influences sperm quality and reproduction in Anopheles culicifacies

Elucidating the biological and molecular mechanisms that govern male fertility and mating behavior in mosquitoes is critical for optimizing genetic and sterile insect technique-based vector control strategies. Here, we examined age-related changes in male reproductive capacity in Anopheles culicifacies, using female egg output as an indirect indicator of male fertility. Our results demonstrated that male reproductive age follows a non-linear pattern of fertility. Morphometric analysis from emergence to day 13 post-eclosion revealed a strong correlation between seminal vesicle capacity and female fecundity, suggesting that age-dependent gonadal development directly influences reproductive potential. At the molecular level, we identified AcLITAF6 as a key regulator of male reproductive homeostasis. RNAi-mediated knockdown of AcLITAF6 impaired apoptosis-associated and phagocytic clearance, reduced sperm viability, and decreased female productive outcomes. Conclusively, we reveal a previously unrecognized role of LITAF in sperm quality control and male reproductive fitness, highlighting AcLITAF6 as a potential target for mosquito population suppression strategies.

developmental biology↗

Subliminal Primes Bias the Spatial Locus of Involuntary Object Naming in a Two-Object Reflexive Imagery Task

Certain conscious contents--such as the covert name of a viewed object--arise involuntarily and resist suppression, a phenomenon captured by the Reflexive Imagery Task (RIT). Whether a subliminal prime can bias which of two simultaneously present objects captures such an involuntary naming response has not been established. We adapted a two-object RIT into a self-contained, browser-based instrument. Thirty-eight adults (M age = 21.6 years, SD = 2.3; 26 female) viewed 24 object pairs and were instructed to fixate a central cross, to refrain from thinking of the objects names, and to click an object whenever its name intruded into awareness. On each trial a masked prime (17 ms, flanked by pattern masks) was either the exact name of one object (Exact Word Prime), a semantic associate of one object (Semantic Prime), or a neutral string (No Prime), defining a primed side per trial. A post-experiment debriefing confirmed that participants noticed the masks but none consciously perceived or could identify the prime words, indicating that the primes were subliminal. Analyses excluded 91 of 912 trials (10.0%) with more than five clicks. The priming effect was robust across measures: an omnibus comparison of clicks across conditions was significant (Friedman {chi}{superscript 2}(2) = 6.59, p = .037); within both prime conditions participants clicked the primed side more than the not-primed side (Exact Word, p = .039; Semantic, p = .005); and the primed-to-not-primed ratio exceeded parity by roughly 57-59% (Laplace-smoothed ratio {approx} 1.58; one-sample Wilcoxon p < .001 for each). A Bayesian Poisson generalized linear mixed model with random participant intercepts confirmed a credible primed-side advantage (incidence rate ratio = 1.72, 95% credible interval [1.57, 1.90]) that did not differ between prime types. No general left/right response bias emerged. An exploratory ight-side x Exact Word Prime interaction was inconsistent across model classes and is reported as hypothesis-generating. The findings indicate that subliminal lexical and semantic primes can steer the spatial locus of involuntary object naming.

neuroscience↗

MTB-LysB1: A Novel Endolysin Against Multidrug-resistant Mycobacterium tuberculosis

The phenotypic plasticity, slow replication, and complex, hydrophobic cell envelope of Mycobacterium tuberculosis contribute to its successful survival as a pathogen and its drug tolerance. Consequently, the global threat of multidrug-resistant Tuberculosis (MDR-TB), coupled with lengthy and highly toxic treatment regimens, necessitates the development of innovative treatment solutions. Mycobacteriophages are natural viruses of mycobacteria that typically encode two endolysins, which cooperatively facilitate host cell lysis at the end of the lytic life cycle: LysA, a peptidoglycan hydrolase, and LysB, a lipolytic enzyme, targeting the mycolylarabinogalactan-peptidoglycan complex. Their precise and efficient lytic activity, along with their low propensity to induce resistance, make them, particularly LysBs, promising candidates for new treatment solutions. In this study, we report MTB-LysB1, a novel LysB enzyme from an F1 sub-cluster mycobacteriophage isolated from our laboratory collection. While studying its structural features by comparing the modelled structure with representative mycobacteriophage LysB homologues, we found that the /{beta}-hydrolase fold and key motifs are conserved. Also, we identified putative membrane-interaction motifs that may play a role in LysB1s cell permeation. Significantly, we found MTB-LysB1 to be active against both drug-susceptible and multidrug-resistant (MDR) M. tuberculosis strains at nanomolar concentrations, comparable to the well-characterised D29 LysB reference enzyme. Beyond its standalone activity, MTB-LysB1 exhibits an additive effect when combined with the TB drugs rifampicin and moxifloxacin, and co-administration reduces the drugs minimum inhibitory concentrations (MICs), which holds clinical significance. By structurally damaging the mycobacterial cell wall, the enzyme appears to act as a permeability enhancer for the chemotherapeutic drugs, thereby improving antibiotic efficacy. Collectively, our findings position the enzyme not only as a novel antimycobacterial agent but also provide a structural framework for its rational engineering as a promising next-generation adjunct to TB drug regimens. HighlightsO_LIA novel F1 sub-cluster phage-derived LysB is discovered and characterised using integrated computational, biochemical and microbiological methods. C_LIO_LIAlphaFold2 modelling, molecular dynamics simulations and comparative structural analyses revealed an /{beta}-hydrolase fold with conserved catalytic and membrane-interaction features. C_LIO_LIThe enzyme exhibited high esterase activity, thermal stability and potent lytic activity against Mycobacterium tuberculosis. C_LIO_LIAn additive effect with TB drugs rifampicin and moxifloxacin highlights MTB-LysB1s potential as an adjunct therapeutic. C_LI

microbiology↗

Targeting CDK12/CYCLIN K induces HIV gene activation and latency reversal which is mediated by P-TEFb

The administration of antiretroviral therapy has successfully suppressed the replication of Human immunodeficiency virus and substantially inhibited viral infection. However, HIV still persists in long-lived infected cell reservoirs that are resistant to therapy and to immune clearance, therefore a barrier for elimination of infection. HIV gene expression is tightly regulated by the cellular transcription machinery, where low levels of host and viral transcription factors and epigenetic constrains maintain viral persistence. Here, we show that selective targeting of CDK12/CYCLIN K (CCNK) induces both HIV-specific and a global gene activation program, which is mediated by positive transcription elongation factor b (P-TEFb). Targeting CDK12/CCNK triggers a robust HIV gene expression, accompanied with latency reversal and synergistic reactivation when combined with latency-reversing agents. Mechanistically, CDK12/CCNK inhibition promotes the recruitment of RNA Polymerase II and CDK9 to the viral promoter, accompanied with elevated levels of histone activation makers. Targeting CDK12/ CCNK also exerts a global gene activation program, by releasing P-TEFb from 7SK snRNP, and reshaping the chromatin landscape at promoter-proximal loci and gene bodies. Together, these results uncover a previously unrecognized compensatory interplay between transcriptional kinases that rewires the cellular gene expression program with implications for HIV latency reversal. IMPORTANTO_LIManuscripts submitted to Review Commons are peer reviewed in a journal-agnostic way. C_LIO_LIUpon transfer of the peer reviewed preprint to a journal, the referee reports will be available in full to the handling editor. C_LIO_LIThe identity of the referees will NOT be communicated to the authors unless the reviewers choose to sign their report. C_LIO_LIThe identity of the referee will be confidentially disclosed to any affiliate journals to which the manuscript is transferred. C_LI GUIDELINESO_LIFor reviewers: https://www.reviewcommons.org/reviewers C_LIO_LIFor authors: https://www.reviewcommons.org/authors C_LI CONTACTThe Review Commons office can be contacted directly at: office@reviewcommons.org

microbiology↗

Genetic changes of P. vivax tempers host tissue-specific responses in Anopheles stephensi

In our preceding study (Sharma et al., 2019; BioRxiv) we showed that in the gut lumen Plasmodium vivax follows a unique strategy of immuno-suppression by disabling gut flora proliferation. Here, we further demonstrate that post gut invasion, a shrewd molecular relationship with individual tissues such as midgut, hemocyte, salivary glands, and strategic changes in the genetic makeup of P. vivax favors its survival in the mosquito host. A transient suppression of metabolic machinery by early oocysts, and increased immunity against late oocysts suggested a unique mechanism of gut homeostasis restoration and Plasmodium population regulation. Though a hyper immune response of hemocyte was a key to remove free circulating sporozoites, but a strong suppression of salivary metabolic activities, may favor successful survival of invaded sporozoites. Finally, genetic alteration of P. vivax ensures evasion of mosquito responses. Conclusively, our system-wide RNAseq analysis provides first genetic evidences of direct mosquito-Plasmodium interaction and establishes a functional correlation.\n\nAuthor SummaryMalaria transmission dynamics is heavily influenced by mosquito -parasite interaction. When passing through tissue specific barriers, Plasmodium have to compromise by losing its own population, but genetic relation is unknown. To win the developmental race Plasmodium need to overcome two important immuno-physiological barriers. First one accounts an indirect 24-30hr long pre-invasive gut-microbe-parasite interaction in the gut lumen. And second one follows a direct post gut invasive 14-18 days interaction with midgut, hemocyte and salivary glands. During pre-invasive phase of interaction, we showed Plasmodium vivax follows immuno-suppression strategy by restricting microbial growth in the gut lumen. Here, we demonstrate that switch of parasite from one stage to another stage within mosquito vector is accompanied by genetic changes of parasite. Our data suggests genetic makeup change enables the parasite to manipulate the metabolism of mosquito tissues. This strategy not only clear off multifaceted mosquitos tissue specific immune responses, but also favors Plasmodium own survival and transmission. Comprehending this tissue specific interaction between host and parasite at molecular level could provide new tool to intervene the plasmodium life cycle within vector.

genomics↗

Microbiome-Gut-Brain-Axis communication regulates metabolic switch in the mosquito Anopheles culicifacies

Periodic ingestion of a protein-rich blood meal by adult female mosquitoes causes a drastic metabolic change in their innate physiological status, which is referred to as metabolic switch. Although the down-regulation of olfactory factors is key to restrain host-attraction, how the gut metabolic switch modulates brain functions, and resilience physiological homeostasis remains unexplored. Here, we demonstrate that the protein-rich diet induces mitochondrial function and energy metabolism, possibly shifting the brains engagement to manage organismal homeostasis. A dynamic expression pattern of neuro-signaling and neuro-modulatory genes in both the brain and gut indicates an optimal brain-distant organ communication. Even after decapitation, significant modulation of the neuro-modulator receptor genes as well as quantitative estimation of neurotransmitters (NTs), together confer the guts ability to serve as a second brain. Finally, data on comparative metagenomic analysis and altered NTs dynamics of naive and aseptic mosquitoes provide the initial evidence that gut-endosymbionts are key modulators for the synthesis of major neuroactive molecules. Conclusively, our data establish a new conceptual understanding of microbiome-gut-brain-axis communication in mosquitoes. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=183 SRC="FIGDIR/small/774430v2_ufig1.gif" ALT="Figure 1"> View larger version (43K): org.highwire.dtl.DTLVardef@4fed8corg.highwire.dtl.DTLVardef@17494f3org.highwire.dtl.DTLVardef@df1cd7org.highwire.dtl.DTLVardef@1de7923_HPS_FORMAT_FIGEXP M_FIG Graphical abstract C_FIG HighlightsO_LIHighly proteinaceous blood meal uptake causes gut metabolic switch activity in mosquitoes. C_LIO_LIGuts calling shifts the brains administrative function from external communication to inter-organ management. C_LIO_LI Gut, as a Second brain plays a crucial role in the maintenance of physiological homeostasis. C_LIO_LIMetabolic switch and proliferation of symbiotic bacteria establish microbiome-gut-brain axis communication in mosquitoes. C_LI

animal behavior and cognition↗

Altered gut microbiota and immunity defines Plasmodium vivax survival in Anopheles stephensi

Blood feeding-enriched gut-microbiota boosts mosquitoes anti-Plasmodium immunity. Here, we ask how Plasmodium vivax alters microbiota, anti-Plasmodial immunity and impact tripartite Plasmodium-mosquito-microbiota interactions in the gut lumen. Using a metagenomics analysis, we predominantly detect Elizabethkingia meningitis and Pseudomonas sps. in naive mosquitoes. Naive blood fed gut shows a heightened presence of Elizabethkingia, Pseudomonas and Serratia. A parallel RNAseq analysis of blood-fed midguts identify Elizabethkingia-transcripts, which may have role in iron metabolism. Post, a Plasmodium vivax infected blood-meal, however, we do not detect bacterial until circa 36 hours. Intriguingly, transcriptional expression of a selected array of antimicrobial arsenal cecropins 1-2, defensin-1 and gambicin remains low during the first 36 hours-a time frame when ookinietes/early oocysts invade gut. We conclude during the preinvasive phase, Plasmodium vivax outcompetes midgut-microbiota. Suppression of important immune factors, likely due to altered microbiota, may enhance Plasmodium vivax survival. Additional finding of a novel Wolbachia association warrants further research to design paratransgenesis tools for malaria control.\n\nAuthor SummarySuccessful malaria transmission relies on the competitive interactions of Plasmodium and mosquitos tissue specific immune potential. Within 24hrs of blood meal gut-microbiota grows exponentially and lead to robust enhancement of mosquito immune response, which is detrimental to parasite survival and development. But the mechanism how Plasmodium manages to evade this pre-invasive immune barrier is not well known. We investigated the influence of tripartite gut-microbiome-parasite interaction on human malaria parasite Plasmodium vivax in its natural/native vector Anopheles stephensi. Surprisingly we found that infectious blood meal lead to dramatic suppression in gut-bacteria population, a plausible strategy of P. vivax ookinetes to avoid immune responses. Our study suggests that for its own survival Plasmodium vivax causes early suppression of bacterial population, possibly by scavenging Fe from the blood meal which is indispensable for bacterial growth. Disruption and manipulation of this gut-microbe-interaction may help to design new paratransgenesis molecular tool for malaria control.

genomics↗

A synergistic transcriptional regulation of olfactory genes derives complex behavioral responses in the mosquito Anopheles culicifacies

Decoding the molecular basis of host seeking and blood feeding behavioral evolution/adaptation in the adult female mosquito may provide an opportunity to design new molecular strategy to disrupt human-mosquito interactions. However, despite the great progress in the field of mosquito olfaction and chemo-detection, little is known that how the sex-specific specialization of the olfactory system enables adult female mosquitoes to derive and manage complex blood feeding associated behavioral responses. A comprehensive RNAseq analysis of prior and post blood meal olfactory system of An. culicifacies mosquito revealed that a minor but unique change in the nature and regulation of key olfactory genes play a pivotal role in managing diverse behavioral responses. Age dependent transcriptional profiling demonstrated that adult female mosquitos chemosensory system gradually learned and matured to drive the host-seeking and blood feeding behavior at the age of 5-6 days. A zeitgeber time scale expression analysis of Odorant Binding Proteins (OBPs) unravels unique association with a late evening to midnight peak biting time. Blood meal-induced switching of unique sets of OBP genes and Odorant Receptors (ORs) expression coincides with the change in the innate physiological status of the mosquitoes. Blood meal follows up experiments provide enough evidence that how a synergistic and concurrent action of OBPs-ORs may drive prior and post blood meal complex behavioral events. Finally, tissue-specific gene expression analysis and molecular modelling predicted two uncharacterized novel sensory appendages proteins (SAP-1 & SAP2) unique to An. culicifacies mosquito and may play a central role in the host-seeking behavior.\n\nSignificanceEvolution and adaptation of blood feeding behavior not only favored the reproductive success of adult female mosquito but also make them an important disease vectors. Immediately after emergence, an environmental exposure may favor the broadly tuned olfactory system of mosquitoes to derive complex behavioral responses. But, how these olfactory derived genetic factors manage female specific pre and post blood meal associated complex behavioral responses are not well known. We unraveled synergistic actions of olfactory factors governs an innate to prime learning strategy to facilitate rapid blood meal acquisition and downstream behavioral activities. A species-specific transcriptional profiling and an in-silico analysis predict novel sensory appendages protein, as a unique target to design disorientation strategy against the mosquito Anopheles culicifacies.

animal behavior and cognition↗