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Biology subjects

Scheer, J.

Publications and source records attributed to Scheer, J..

2 recordsLinked to original sources

Bridging biomolecular modalities for knowledge transfer in bio-language models

In biology, messenger RNA (mRNA) plays a crucial role in gene expression and protein synthesis. Accurate predictive modeling of mRNA properties can greatly enhance our understanding and manipulation of biological processes, leading to advancements in medical and biotechnological applications. Utilizing bio-language foundation models allows for leveraging large-scale pretrained knowledge, which can significantly improve the efficiency and accuracy of these predictions. However, mRNA specific foundation models are notably limited posing challenges for efficient predictive modeling in mRNA-focused tasks. In contrast, DNA and protein modalities have numerous general-purpose foundation models trained on billions of sequences. This paper explores the potential for adaptation of existing DNA and protein bio-language models for mRNA-focused tasks. Through experiments using various mRNA datasets curated from both public domain and internal proprietary database, we demonstrate that pre-trained DNA and protein models can be effectively transferred for mRNA-focused tasks using various adaptation techniques such as probing, full-rank, and low-rank finetuning. In addition, we identify key factors that influence successful adaptation, offering guidelines on when general-purpose DNA and protein models are likely to perform well for mRNA-focused tasks. We further assess the impact of model size on adaptation efficacy, finding that medium-scale models often outperform larger ones for cross-modal knowledge transfer. We conclude that by leveraging the interconnectedness of DNA, mRNA, and proteins, as outlined by the central dogma of molecular biology, the knowledge in foundation models can be effectively transferred across modalities, significantly enhancing the repertoire of computational tools available for mRNA analysis.

bioinformatics↗

The translocation activity of Rad54 reduces crossover outcomes during homologous recombination

Homologous recombination (HR) is a template-based DNA double-strand break repair pathway that requires the selection of an appropriate DNA template for repair during the homology search stage of HR. Failure to execute the homology search quickly and efficiently can result in complex intermediates that generate genomic rearrangements, a hallmark of human cancers. Rad54 is an ATP dependent DNA motor protein that functions during the homology search by regulating the recombinase Rad51. How this regulation reduces genomic rearrangements is currently unknown. To better understand how Rad54 can prevent genomic rearrangements, we evaluated several amino acid mutations in Rad54 that were found in the COSMIC database. COSMIC is a collection of amino acid mutations identified in human cancers. These substitutions led to reduced Rad54 function and the discovery of a conserved motif in Rad54. Through genetic, biochemical, and single-molecule approaches, we show that disruption of this motif leads to failure in stabilizing early strand invasion intermediates, causing loss-of-heterozygosity rearrangements. Our study also suggests that the translocation rate of Rad54 is a determinant in balancing genetic exchange. This mechanism is likely fundamental to eukaryotic biology.

biochemistry↗