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Roch, W.

Publications and source records attributed to Roch, W..

2 recordsLinked to original sources

Computational Profiling and Pathogenicity Assessment of VHL Missense Mutations

Mutations in the VHL tumor suppressor gene promote tumorigenesis by stabilizing HIF-1. In this study, we investigated the functional impact of VHL missense mutations using AlphaMissense pathogenicity scores, protein stability simulations, and molecular dynamics. AlphaMissense identified high pathogenicity scores for residues 60-200, including the {beta}-domain and HIF-binding domain, suggesting these regions are critical for VHL's tumor suppressor function. We categorized the mutations into two groups: those that primarily destabilize protein folding and those that likely disrupt VHL-HIF-1 binding. FoldX stability simulations revealed high {Delta}{Delta}G values for both groups, with proline substitutions exerting significant structural stress. Structural modeling confirmed that these mutations disrupt secondary structures, particularly {beta}-sheets. Molecular dynamics simulations showed that the VHL monomer is flexible and unstable in several regions, whereas the VHL-HIF complex, particularly the HIF-binding domain, exhibits enhanced stability. Mutational scanning revealed that bulky amino acid substitutions, such as tryptophan, cause notable destabilization. Interestingly, some mutations predicted to be structurally stable were still classified as pathogenic by AlphaMissense and validated in the literature, suggesting that pathogenicity may arise from subtle functional impairments rather than just structural instability. These findings underscore the value of combining machine learning, structural simulations, and experimental data to predict and interpret the pathogenicity of VHL mutations.

bioinformatics↗

Preadipocyte uncoupling protein 1 expression invoked by fibroblast growth factors imprints on post-differentiation white and brown adipocyte function

The presence of uncoupling protein 1 (Ucp1) is a hallmark of thermogenic adipocytes and enables heat production by dissipating energy from mitochondrial proton motive force as heat. The purpose of its recently discovered presence in preadipocytes in response to certain fibroblast growth factors remains elusive. In this study, we systematically investigated the potential of all paracrine fibroblast growth factors (FGFs) to invoke Ucp1 expression in murine preadipocytes derived from interscapular brown and inguinal white adipose tissue. The factors FGF2, FGF4, FGF8, and FGF9 induced Ucp1 expression in undifferentiated preadipocytes, with FGF2 acting most potently and rapidly. This premature Ucp1 induction did not translate into increased Ucp1 protein abundance or thermogenic activity after full adipogenic differentiation. Notably, preadipocyte treatment with FGFs and concomitant Ucp1 expression led to a sustained suppression of interferon-stimulated genes after differentiation. Preadipocyte Ucp1 was required and sufficient for this lasting imprint. Thus, Ucp1 in preadipocytes programs post-differentiation inflammatory status.

molecular biology↗