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Biology subjects

Byrne, F.

Publications and source records attributed to Byrne, F..

3 recordsLinked to original sources

Distinct functions of PBRM1 and BAP1 reconcile the course of kidney cancer evolution and disease progression

Clear cell renal cell carcinoma (ccRCC) progresses along two predominant evolutionary trajectories, defined by PBRM1 ([~]40%) or BAP1 ([~]15%) mutations on a VHL-inactivated background. They have distinct patterns of evolutionary tempo and mode, and vastly different clinical outcomes, yet the underlying genotype-specific molecular phenotypic programmes are unknown. We established a patient-derived preclinical model biobank that captures the genetic diversity of ccRCC. Through integrative analyses of preclinical models and tumour bulk and single cell profiling, we identified transcriptional and epigenetic changes specific to PBRM1- and BAP1-driven ccRCC. Modelling PBRM1 loss in vitro demonstrates that it reinforces renal lineage identity and maintains progenitor-like cell state. In contrast, BAP1 loss drives inflammatory signalling and chromosomal instability. These insights reconcile the distinct evolutionary modes (branched versus punctuated), tempo (slow versus fast) and clinical outcomes associated with PBRM1 and BAP1 mutations, respectively, establishing a framework for patient stratification and genotype-directed therapeutic development.

cancer biology↗

Structural basis for synergistic antibody protection against the essential malaria invasion complex protein RIPR

Plasmodium falciparum RH5-interacting protein (RIPR) is central to the essential PTRAMP-CSS-RIPR-CyRPA-RH5 (PCRCR)-complex; a leading target of blood-stage malaria vaccines. However, mechanisms whereby anti-RIPR antibodies inhibit parasite invasion are poorly understood. Here, we characterise 83 human IgG mAbs from RIPR-vaccinated Kymouse platform mice. Single mAbs have minimal neutralising activity, however, high-level synergistic inhibition is observed with pools of mAbs targeting the RIPR-Tail region. Structural characterisation and molecular dynamics simulations of RIPR-Tail show that mAbs targeting EGF-like domains 6-8 (RIPREGF (6-8)), but not EGF-like domains 9-10 or the C-terminal domain (RIPREGF (9-10)-CTD), synergise to constrain the RIPR-Tail conformation. The same antibodies dissociate PTRAMP-CSS from RIPR, thereby enabling anti-RIPREGF (9-10)-CTD mAbs or anti-CSS sdAbs to bind and potentiate anti-RIPREGF (6-8) IgG. Addition of these mAbs to IgG from humans immunised with the R78C (RIPREGF (7-8)-CyRPA) candidate vaccine enhances malaria growth inhibition. These data provide a framework to guide next-generation blood-stage malaria vaccine design.

immunology↗

Chromosome-Specific Aneuploidy Engineering via dCas9-Induced Centromeric Chromatin Relaxation

Aneuploidy, the gain or loss of chromosomes, is prevalent in both normal and disease conditions, however, experimental approaches to engineer and study aneuploidy remain limited, leaving its functional significance under-characterized. Here, we present CRISPR-Taiji (CRISPRt), an efficient method for inducing chromosome-specific mis-segregation and aneuploidy generation across all 24 human chromosomes via dead Cas9 (dCas9)-induced centromeric chromatin relaxation. Using CRISPRt with scRNA-seq, we generated the first comprehensive transcriptomic alteration landscape of nearly all autosomal aneuploidies at chromosome-arm resolution. This genotype-phenotype map provides causal evidence linking recurrent aneuploidies in clear cell renal cell carcinoma (ccRCC) to molecular and clinical phenotypes observed in patient tumors. Notably, chromosome 3(p) loss, the ccRCC initiating event, specifically drives strong interferon signaling activation, offering novel insights into ccRCC tumorigenesis and immune modulation. Overall, we establish CRISPRt as a simple, efficient and scalable approach for chromosome-specific aneuploidy engineering and characterization in preclinical models to advance aneuploidy research across diverse biological contexts.

genomics↗