Biology subjects

Bojko, J.

Publications and source records attributed to Bojko, J..

5 recordsLinked to original sources

bioRxiv2025

Developing an approach to list bryophytes of conservation interests for England's Local Nature Recovery Strategies

Biodiversity is globally declining, and the United Kingdom (UK) recognised as one of the most nature-depleted countries. With an aim to restore ecosystems, the UK has initiated a policy of Local Nature Recovery Strategies (LNRS), to be published for 48 areas across England. We devised and applied a workflow using open access data to produce preliminary lists of bryophytes of conservation interest for each LNRS area. Our objectives include: (i) to ascertain which LNRS area match the current recording scheme based on Watsonian vice-counties; (ii) to produce data-driven draft lists for each LNRS area, (iii) to compare this list in the Tees Valley area with a species list derived from expert knowledge. Using an inclusion threshold at 90% of surface area, we found that 20 out of the 48 LNRS areas are compatible with the vice-county-based scheme. We determine that LNRS areas included on average 9.3 (+/- 6.9) species threatened by extinction, a supplementary 3.6 (+/- 3.4) species near threatened and, adding nationally rare or scarce species, a total of 66.3 (+/- 35.1) species. A case study based on the Tees Valley revealed an overall good match between data and expert driven species lists, despite discrepancies relating to geographical attributions near boundaries and additional species solely selected by expert opinion. It is anticipated that the preliminary lists produced could save valuable time to local experts when working towards LNRS bryophyte lists, and that the approach developed will be relevant to other organism groups, supporting effectively LNRSs across England.

ecology↗

bioRxiv2024

YAP engages RIF1 to dampen replication stress in squamous cell carcinoma.

Squamous cell carcinoma cells experience high levels of replication stress due to oncogene-induced cell cycle deregulation. How such cells sustain rapid proliferation despite replication stress is still not fully understood. Here, we discovered, using rapid immunoprecipitation mass spectrometry of endogenous protein (RIME) analysis, that the squamous cell carcinoma oncoprotein YAP engages with RIF1, a key regulator of DNA replication and DNA damage repair under replication stress. RIF1 is highly expressed in human squamous cell carcinoma cell lines and tissues and upregulated during tumour progression. Depletion of RIF1 in squamous cell carcinoma cells exacerbates their endogenous replication stress. Mechanistically, we show that YAP interacts with RIF1 specifically at broken replication forks, and that YAP depletion impairs DNA damage repair under replication stress. Our results thus demonstrate that YAPs oncogenic functions in squamous cancers involve both transcriptional and non-transcriptional mechanisms, the latter through interaction with RIF1 to dampen replication stress.

cancer biology↗

bioRxiv2024

Genetic and morphological characterization of Metacollinia emscheri n. sp., a novel sanguicolous apostome ciliate of the freshwater amphipods Gammarus pulex and G. fossarum

We describe a novel sanguicolous parasitic ciliate, Metacollinia emscheri n. sp., found in the freshwater amphipods Gammarus pulex and G. fossarum. This ciliate infected up to 20% of the amphipods collected in a German stream catchment, the Boye, a tributary of the river Emscher. The ciliate showed morphological characteristics fitting the genus Metacollinia. Different life stages of variable size occurred simultaneously in the hemocoel throughout the hosts body. The tomont had 40-47 slightly spiraled kineties, a non-ciliated cortical band, a large macronucleus, and contractile vacuoles arranged in rows or scattered throughout the cytoplasm. The protomites/tomites with nine somatic kineties presented evidence of the buccal kineties x, y, and z reminiscent of those of the order Foettingeriida. Phylogenetic analyses of the 18S rRNA and COI regions confirm the ciliate placement in the Collinidae and a close relatedness to the type species of the genus Metacollinia, Metacollinia lucensis. Hence, we formally describe this parasite as Metacollinia emscheri n. sp. The systemic infections observed in histological preparations and the pathogenicity of Metacollinia emscheri n. sp. suggest that this parasite might influence host population dynamics. Given the ecological importance of amphipods as keystone species in freshwater ecosystems, an outbreak of this parasite might indirectly impact ecosystem functioning.

ecology↗

bioRxiv2024

PRMT5 inhibition preferentially targets MYCN-amplified neuroblastoma via altered transcriptional and splicing programmes regulating key cancer cell fitness pathways.

About 50% of poor prognosis neuroblastoma arises due to MYCN over-expression. We previously demonstrated that MYCN and PRMT5 proteins interact and PRMT5 knockdown led to apoptosis of MYCN amplified (MNA) neuroblastoma. Here we evaluate PRMT5 inhibitors GSK3203591/GSK3326593 as targeted therapeutics for MNA neuroblastoma and show MYCN-dependent growth inhibition and apoptosis. RNAseq revealed dysregulated MYCN transcriptional programmes and altered mRNA splicing, converging on key regulatory pathways such as DNA damage response, epitranscriptomics and cellular metabolism. Metabolic tracing showed glutamine metabolism was impeded following GSK3203591 treatment, which disrupted the MLX/Mondo nutrient sensors via intron retention of MLX mRNA. Glutaminase (GLS) protein was decreased by GSK3203591 despite unchanged transcript levels, suggesting post-transcriptional regulation. We demonstrate the RNA methyltransferase METTL3 and cognate reader YTHDF3 proteins are lowered following splicing alterations; accordingly, we observed hypomethylation of GLS mRNA and decreased GLS following YTHDF3 knockdown. In vivo efficacy of GSK3326593 was confirmed by increased survival of Th-MYCN mice together with splicing events and protein decreases consistent with in vitro data. Our study supports the spliceosome as a key vulnerability of MNA neuroblastoma and rationalises PRMT5 inhibition as a targeted therapy. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=133 SRC="FIGDIR/small/582087v2_ufig1.gif" ALT="Figure 1"> View larger version (54K): org.highwire.dtl.DTLVardef@1ac6b5org.highwire.dtl.DTLVardef@1eb9520org.highwire.dtl.DTLVardef@18b980corg.highwire.dtl.DTLVardef@1ab46e0_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2018

White Spot Syndrome Virus and the Caribbean Spiny Lobster, Panulirus argus: Susceptibility and Behavioral Immunity

The Caribbean spiny lobster Panulirus argus is susceptible to infection by Panulirus argus Virus 1 (PaV1), the only virus known to naturally infect any lobster species. However, P. argus is able to mitigate PaV1 transmission risk by avoiding infected individuals. White Spot Syndrome Virus (WSSV) has a particularly wide host range. WSSV has not been documented in wild populations of spiny lobsters, but has been experimentally transmitted to six other lobster species from the genus Panulirus spp. While WSSV has been detected intermittently in wild populations of shrimp in the Caribbean region, the risk to P. argus has not been evaluated. Potential emergence of the disease could result in fisheries losses and ecological disruption. To assess the risk to P. argus, we tested its susceptibility to WSSV via injection and waterborne transmission. We also tested whether healthy lobsters can detect and avoid conspecifics with qPCR-quantifiable WSSV infections. We found P. argus to be highly susceptible to WSSV via intramuscular injection, with mortality reaching 88% four weeks post inoculation. Panulirus argus was also susceptible to WSSV via waterborne transmission, but WSSV burden was low after four weeks via qPCR. Behavioral assays indicated that P. argus can detect and avoid conspecifics infected with WSSV and the avoidance response was strongest for the most heavily infected individuals - a response comparable to PaV1-infected conspecifics. Panulirus argus is the first spiny lobster found to be susceptible to WSSV in the Americas, but it is possible that a generalized avoidance response by healthy lobsters against infected conspecifics provides a behavioral defense and may reduce WSSV infection potential and prevalence. Such avoidance may extend to other directly transmitted pathogens in spiny lobster populations preventing them from becoming common in their population.\n\nAuthor SummaryErica P. Ross is a PhD candidate at the University of Florida, studying the disease ecology of the Caribbean spiny lobster, with a focus on chemosensory ecology. Donald C. Behringer is an associate professor at the University of Florida and his research focuses on disease ecology, epidemiology, and fishery ecology, with a focus on crustaceans and other marine invertebrates. Jamie Bojko received his PhD from the University of Leeds and is currently a post-doctorate associate at the University of Florida studying experimental and systemic crustacean pathology.

ecology↗