The Molecular Frequency, Conservation and Role of Reactive Cysteines in Plant Lipid Metabolism.

Cysteines (Cys) are chemically reactive amino acids containing sulfur that play diverse roles in plant biology. Recent proteomics investigations in Arabidopsis thaliana have revealed the presence of thiol post-translational modifications (PTMs) in several Cys residues. These PTMs are presumed to impact protein structure and function, yet mechanistic data regarding the specific Cys susceptible to modification and their biochemical relevance remain limited. To help address these limitations, we have conducted a wide-ranging analysis by integrating published datasets encompassing PTM proteomics (comparing S-sulfenylation, persulfidation, S-nitrosylation and S-acylation), genomics and protein structures, with a specific focus on proteins involved in plant lipid metabolism. The prevalence and distribution of modified Cys residues across all analyzed proteins is diverse and multifaceted. Nevertheless, by combining an evaluation of sequence conservation across 100+ plant genomes with AlphaFold-generated protein structures and physicochemical predictions, we have unveiled structural propensities associated with Cys modifications. Furthermore, we have identified discernible patterns in lipid biochemical pathways enriched with Cys PTMs, notably involving beta-oxidation, jasmonic acid biosynthesis, fatty acid biosynthesis and wax biosynthesis. These collective findings provide valuable insights for future investigations targeting the mechanistic foundations of Cys modifications and the regulation of modified proteins in lipid metabolism and other metabolic pathways.

snRNA-seq of human cutaneous neurofibromas before and after selumetinib treatment implicates role of altered Schwann cell states, inter-cellular signaling, and extracellular matrix in treatment response.

Neurofibromatosis Type 1 (NF1) is caused by loss of function variants in the NF1 gene. Most patients with NF1 develop skin lesions called cutaneous neurofibromas (cNFs). Currently the only approved therapeutic for NF1 is selumetinib, a mitogen -activated protein kinase (MEK) inhibitor. The purpose of this study was to analyze the transcriptome of cNF tumors before and on selumetinib treatment to understand both tumor composition and response. We obtained biopsy sets of tumors both pre- and on- selumetinib treatment from the same individuals and were able to collect sets from four separate individuals. We sequenced mRNA from 5844 nuclei and identified 30,442 genes in the untreated group and sequenced 5701 nuclei and identified 30,127 genes in the selumetinib treated group. We identified and quantified distinct populations of cells (Schwann cells, fibroblasts, pericytes, myeloid cells, melanocytes, keratinocytes, and two populations of endothelial cells). While we anticipated that cell proportions might change with treatment, we did not identify any one cell population that changed significantly, likely due to an inherent level of variability between tumors. We also evaluated differential gene expression based on drug treatment in each cell type. Ingenuity pathway analysis (IPA) was also used to identify pathways that differ on treatment. As anticipated, we identified a significant decrease in ERK/MAPK signaling in cells including Schwann cells but most specifically in myeloid cells. Interestingly, there is a significant decrease in opioid signaling in myeloid and endothelial cells; this downward trend is also observed in Schwann cells and fibroblasts. Cell communication was assessed by RNA velocity, Scriabin, and CellChat analyses which indicated that Schwann cells and fibroblasts have dramatically altered cell states defined by specific gene expression signatures following treatment (RNA velocity). There are dramatic changes in receptor-ligand pairs following treatment (Scriabin), and robust intercellular signaling between virtually all cell types associated with extracellular matrix (ECM) pathways (Collagen, Laminin, Fibronectin, and Nectin) is downregulated after treatment. These response specific gene signatures and interaction pathways could provide clues for understanding treatment outcomes or inform future therapies.

The UTHealth Houston Adult Cardiovascular Genomics Certificate Program: Efficacy and Impact on Healthcare Professionals.

Background: The demand for genetic services has outpaced the availability of resources, challenging clinicians untrained in genetic integration into clinical decision-making. The UTHealth Adult Cardiovascular Genomics Certificate (CGC) program trains non-genetic healthcare professionals to recognize, assess, and refer patients with heritable cardiovascular diseases. This asynchronous online course includes 24 modules in three tiers of increasing complexity, using realistic clinical scenarios, interactive dialogues, quizzes, and tests to reinforce learning. We hypothesized that the CGC will increase genomic competencies in this underserved audience and encourage applying genomic concepts in clinical practice. Methods: Required course evaluations include pre- and post-assessments, knowledge checks in each module, and surveys for module-specific feedback. After 6 months, longitudinal feedback surveys gathered data on the long-term impact of the course on clinical practice and conducted focused interviews with learners. Results: The CGC was accredited in September 2022. Principal learners were nurses (24%), nurse practitioners (21%), physicians (16%), and physician assistants. Scores of 283 learners in paired pre- and post-assessments increased specific skills related to recognizing heritable diseases, understanding inheritance patterns, and interpreting genetic tests. Interviews highlighted the CGC's modular structure and linked resources as key strengths. Learners endorsed confidence to use genetic information in clinical practice, such as discussing genetic concepts and risks with patients and referring patients for genetic testing. Learners were highly likely to recommend the CGC to colleagues, citing its role in enhancing heritable disease awareness. Conclusions: The CGC program effectively empowers non-genetic clinicians to master genomic competencies, fostering collaboration to prevent deaths from heritable cardiovascular diseases, and potentially transforming healthcare education and clinical practice.