Biology subjects

Thenuwara, S.

Publications and source records attributed to Thenuwara, S..

3 recordsLinked to original sources

bioRxiv2025

Rapidly evolved genomic regions shape individual language abilities in present-day humans

Language is a defining feature of our species, yet the genomic changes enabling it remain poorly understood. Despite decades of work since FOXP2s discovery, we still lack a clear picture of which regions shaped language evolution and how variation contributes to present-day phenotypic differences. Using a novel evolutionary stratified polygenic score approach in nearly 40,000 individuals, we find that Human Ancestor Quickly Evolved Regions (HAQERs) are specifically associated with language but not general cognition. HAQERs evolved before the human-Neanderthal split, giving hominins increased binding of Forkhead and Homeobox transcription factors, and show balancing selection across the past 20,000 years. Remarkably, language variants in HAQERs appear more prevalent in Neanderthals and have convergently evolved across vocal-learning mammals. Our results reveal how ancient innovations continue shaping human language.

evolutionary biology↗

bioRxiv2021

CULTURE AND MAINTENANCE OF URINE-DERIVED, 3-DIMENSIONAL CANINE TRANSITIONAL CELL CARCINOMA ORGANOIDS

Bladder cancer is the ninth most common malignancy in the world. Transitional cell carcinoma (TCC), also referred to as urothelial carcinoma (UC) is the most common form of bladder cancer, occurring in 90% of cases. In this study, we explore urine-derived, 3-dimensional, canine TCC organoids as a possible model to study bladder TCC ex vivo. After establishing the cell lines, we subjected the 3D cells to RNA in situ hybridization (RNA-ISH) and cell viability assays. Overall, 3D cell culture from urine samples of TCC diagnosed canines expressed RNA biomarkers in a similar manner to parent tumors via RNA-ISH and showed more sensitivity to cisplatin treatment when compared to 2D human TCC cells. With further experimentation, canine TCC organoids could become an ideal model to study TCC ex vivo.

cancer biology↗

bioRxiv2018

Two Novel Forms of ERG Oscillation in Drosophila: Age and Activity Dependence

Over an animals lifespan, neuronal circuits and systems often decline in an inherently heterogeneous fashion. To compare the age-dependent progression of changes in visual behavior with alterations in retinal physiology, we examined phototaxis and electroretinograms (ERGs) in a wild-type D. melanogaster strain (Canton-S) across their lifespan. In aged flies (beyond 50% median lifespan), we found a marked decline in phototaxis, while motor coordination was less disrupted, as indicated by relatively stronger negative geotaxis. These aged flies displayed substantially reduced ERG transient amplitudes while the receptor potentials (RP) remained largely intact. Using a repetitive light flash protocol, we serendipitously discovered two forms of activity-dependent oscillation in the ERG waveforms of young flies: \"light-off and \"light-on\" oscillations. After repeated 500 ms light flashes, light-off oscillations appeared during the ERG off-transients (frequency: 50-120 Hz, amplitude: ~1 mV). Light-on oscillations (100-200 Hz, ~0.3 mV) were induced by a series of 50 ms flashes, and were evident during the ERG on-transients. Both forms of oscillation were observed in other strains of D. melanogaster(Oregon-R, Berlin), additional Drosophila species (funerbris, euronotus, hydei, americana), and were evoked by a variety of light sources. Both light-off and light-on oscillations were distinct from previously described ERG oscillations in visual mutants, such as rosA, in terms of location within the waveform and frequency. However, within rosA mutants, light-off oscillations, but not light-on oscillations could be recruited by the repetitive light flash protocol. Importantly though, we found that both forms of oscillation were rarely observed in aged flies. Although the physiological bases of these oscillations remain to be elucidated, they may provide important clues to age-related changes in neuronal excitability and synaptic transmission.

neuroscience↗