Biology subjects

Russell, B. D.

Publications and source records attributed to Russell, B. D..

4 recordsLinked to original sources

bioRxiv2026

Starve-Feed Cycles Direct Quiescence to Proliferation Transitions in Drosophila Follicle Stem Cells via Transcriptional Regulation

Stem cell quiescence is a reversible state in which cells temporarily exit the cell cycle but remain poised to reenter, on cue. Robust protection of the balance between stem cell quiescence and proliferation (Q->P) is critical for long-term tissue health. Proliferation without proper resources drives disease states including cancer or birth defects. Conversely, extended periods of quiescence can lead to irreversible senescence, causing stem cell loss, aging symptoms, and vulnerability to oncogenic transformation. Diet is a central regulator of Q->P. Tissue stem cells are particularly impacted, entering periods of quiescence during nutrient restriction, with rapid induction of proliferation upon feeding. We demonstrated previously that the Hedgehog (Hh) signaling pathway is necessary and sufficient for controlling Q->P responses to dietary changes in epithelial Follicle Stem Cells (FSCs) in the fly ovary. The Hh effector, Cubitus Interruptus (Ci), is a transcriptional regulator that mediates the feeding response. To identify Ci-induced Q->P regulators, we labeled transcripts that are induced in FSCs during the 6-hour Q->P timecourse using thiouracil tagging (TU-tagging), and sequenced TU-tagged messages versus Input to prioritize candidates. Unexpectedly, cell cycle regulators were not induced, suggesting that other mechanisms control Q->P in FSCs. We describe a sequential screening approach that uncovered seven novel, feeding-dependent Q->P regulators, including a cholesterol transporter and, surprisingly, glial and neuronal regulators. Our results highlight the importance of dynamic regulation of gene expression for translation of dietary signals by stem cells, uncovering new pathways for mechanistic investigation.

genetics↗

bioRxiv2024

Millennial-scale societal shifts drive the widespread loss of a marine ecosystem

Degradation of marine ecosystems by human activities is a global problem, with only recent recognition that exploitation of ecosystems over millennia can result in their functional extinction and loss from human memory. To reconstruct the historical distribution of oyster reefs in China, and the context behind loss, we extracted information from archaeological records and historical documents (pre-modern Chinese literature, administration reports, art, maps, newspapers) spanning [~]7600 years, then constrained records with past coastlines and habitable environmental conditions. Oyster reefs were extensively distributed along >750 km of coastline in the Pearl River Delta, and their exploitation underpinned the regions development into Chinas first economic hub in the 6th century. Millennial-scale overexploitation alongside societal shifts were central in their regional extirpation by the 19th century, but the enduring cultural importance of oysters is maintained by aquaculture expansion. Informed conservation practices can be developed from reconstructing the temporal interplay between human societies and the natural environment.

ecology↗

bioRxiv2022

Global success in oyster reef restoration despite ongoing recovery debt

Habitat destruction and biodiversity loss from exploitation of ecosystems have led to increased restoration and conservation efforts worldwide. Disturbed ecosystems accumulate a recovery debt - the accumulated loss of ecosystem services - and quantifying this debt presents a valuable tool to develop better ecosystem restoration practices. Here, we quantified the ongoing recovery debt following structural restoration of oyster habitats, one of the most degraded marine ecosystems worldwide. We found that whilst restoration initiates a rapid increase in biodiversity and abundance of 2- to 5-fold relative to unrestored habitat, recovery rate decreases substantially within a few years post-restoration and accumulated global recovery debt persists at >35% per annum. Therefore, while efficient restoration methods will produce enhanced recovery success and minimise recovery debt, potential future coastal development should be weighed up against not just the instantaneous damage to ecosystem functions and services but also the potential for generational loss of services and long-term recovery.

ecology↗

bioRxiv2021

The benefits of herbivory outweigh the costs of bioerosion in a eutrophic coral community

Herbivores play an integral part in maintaining the health of coral reefs by suppressing the growth of algae and accumulation of sediment and facilitating coral growth. However, in predator-depleted systems where densities of herbivores are unnaturally high, grazing can have detrimental effects on corals through excessive bioerosion. Yet, these benefits and costs are rarely investigated concurrently, especially in eutrophic systems where grazers may play a disproportionate role. We used a year-long exclusion experiment to elucidate the effect of natural densities of the dominant herbivore (the sea urchin Diadema setosum) on coral communities in a heavily fished and eutrophic system (Hong Kong, China). To assess benthic community response to grazing, we monitored the survival and growth of three locally abundant coral species (Pavona decussata, Platygyra carnosus and Porites sp.), algal and sediment accumulation, and bioerosion of coral skeletons across seasons. We found that urchins maintained our experimental coral assemblages, and when excluded, there was a 25 to 75-fold increase in algal-sediment matrix accumulation. Contrary to predictions, there was no general response of corals to urchin presence; Porites sp. survivorship increased while P. decussata was unaffected, and growth rates of both species was unchanged. Surprisingly, P. carnosus experienced higher mortality and bioerosion of up to 33% of their buoyant weight when urchins were present. Therefore, under natural densities, sea urchins clear substrate of algae and sediment, increase survival, maintain growth rates and health of coral assemblages, yet can accelerate the bioerosion of species with porous skeletons following mortality.

ecology↗