Biology subjects

Gowri, V.

Publications and source records attributed to Gowri, V..

4 recordsLinked to original sources

bioRxiv2026

Intergenerational shifts in innate odour preferences upon odour injections in Bicyclus anynana butterfly larvae

How insects transmit food odour preferences acquired during the larval stage to their offspring is unknown. Bicyclus anynana butterfly larvae can learn to prefer a banana-smelling odour, isoamyl acetate (IAA), via feeding on coated leaves, or simply via haemolymph transfusions from an IAA-fed animal, and transmit this preference to their naive offspring. Here we explore how larvae respond to different concentrations of IAA using olfaction choice tests, and how injections of different concentrations of IAA directly into the haemolymph impact odour learning and transmission of learned preferences. We find that naive larvae showed a slight preference towards low concentrations of IAA, and a slight avoidance towards higher concentrations. Injections of IAA at low concentrations directly into the haemolymph led to an increase in preference for IAA, whereas higher concentrations led to an increase in avoidance. Naive offspring inherited the odour preferences of their parents. Finally, injections of IAA at different concentrations into embryos did not alter choices made by hatched larvae. We establish that the same molecule (IAA) can illicit both a preference as well as an aversive reaction when directly injected into the haemolymph, but IAA is not directly implicated in intergenerational inheritance.

animal behavior and cognition↗

bioRxiv2024

Brain and gonadal genes are differentially expressed in Bicyclus anynana butterfly larvae that learned a heritable novel food odor preference

Bicyclus anynana butterfly larvae learn to prefer novel odors added to their plant food and transmit those learned preferences to the next generation. However, the molecular mechanisms regulating the inheritance of this acquired preference remain unexplored. Here we examined how larval diet affected gene expression patterns in the larval brain as well as the gonads of adults to explore a potential genetic basis of this inheritance. We fed B. anynana larvae leaves coated with a novel banana odor (isoamyl acetate), or with a control solution, and performed five choice assays on individual larvae during their development to identify individuals that showed a majority preference for the treatment odor they were fed with. We then dissected male and female larval brains, adult spermatophores, or adult oocytes from those individuals, and profiled mRNA in all tissues and micro-RNA (miRNA) expression in oocytes only. Our results show that there are 83 differentially expressed genes (DEGs) across all tissue types in odor and control groups, of which 23 play roles in metabolism, transcription, response to various chemical stimuli, and olfactory pathways. MiRNAs did not differ in expression across diet treatments, but we discovered 57 novel miRNAs in oocytes. The DEGs in gonads are potential epigenetic factors that can regulate the inheritance of a learned odor preference. Still, caution is required as there was no overlap between DEGs across male and female brains, as well as male and female gonads.

genomics↗

bioRxiv2023

Hemolymph transfusions transfer heritable learned novel odor preferences to naive larvae of Bicyclus anynana butterflies

The mechanisms whereby environmental experiences of parents are transmitted to their offspring to impact their behavior and fitness are poorly understood. Previously, we showed that naive Bicyclus anynana butterfly larvae, whose parents fed on a normal plant feed but coated with a novel odor, inherited a learned preference towards that odor, which had initially elicited avoidance in the naive parents. Here, we performed simple hemolymph transfusions from odor-fed and control-fed larvae to naive larval recipients. We found that larvae injected with hemolymph from odor-fed donors stopped avoiding the novel odor, and their naive offspring preferred the odor more, compared to the offspring of larvae injected with control hemolymph. These results indicate that factors in the hemolymph, potentially the odor molecule itself, play an important role in odor learning and preference transmission across generations. Furthermore, this mechanism of odor preference inheritance, mediated by the hemolymph, bypasses the peripheral odor-sensing mechanisms taking place in the antennae, mouthparts, or legs, and may mediate host plant switching and diversification in the Lepidoptera or more broadly across insects.

animal behavior and cognition↗

bioRxiv2021

Butterfly eyespots evolved via co-option of the antennal gene-regulatory network

Butterfly eyespots are beautiful novel traits with an unknown developmental origin. Here we show that eyespots likely originated via co-option of the antennal gene-regulatory network (GRN) to novel locations on the wing. Using comparative transcriptome analysis, we show that eyespots cluster with antennae relative to multiple other tissues. Furthermore, three genes essential for eyespot development (Distal-less (Dll), spalt (sal), and Antennapedia (Antp)) share similar regulatory connections as those observed in the antennal GRN. CRISPR knockout of cis-regulatory elements (CREs) for Dll and sal led to the loss of eyespots and antennae, and also legs and wings, demonstrating that these CREs are highly pleiotropic. We conclude that eyespots likely re-used the ancient antennal GRN, a network previously implicated also in the development of legs and wings.

evolutionary biology↗