Unveiling the influence of factor VIII physicochemical properties on hemophilia A phenotype through an in silico methodology

Copyright © 2022. Published by Elsevier B.V..

BACKGROUND AND OBJECTIVES: Hemophilia A (HA) is an X-linked blood disorder. It is caused by pathogenic F8 gene variants, among which missense mutations are the most prevalent. The resulting amino acid substitutions may have different impacts on physicochemical properties and, consequently, on protein functionality. Regular prediction tools do not include structural elements and their physiological significance, which hampers our ability to functionally link variants to disease phenotype, opening an ample field for investigation. The present study aims to elucidate how physicochemical changes generated by substitutions in different protein domains relate to HA, and which of these features are more consequential to protein function and its impact on HA phenotype.

METHODS: An in silico evaluation of 71 F8 variants found in patients with different HA phenotypes (mild, moderate, severe) was performed to understand protein modifications and functional impact. Homology modeling was used for the structural analysis of physicochemical changes including electrostatic potential, hydrophobicity, solvent-accessible/excluded surface areas, disulfide disruptions, and substitutions indexes. These variants and properties were analyzed by hierarchical clustering analysis (HCA) and principal component analysis (PCA), independently and in combination, to investigate their relative contribution.

RESULTS: About 69% of variants show electrostatic changes, and almost all show hydrophobicity and surface area modifications. HCA combining all physicochemical properties analyzed was better in reflecting the impact of different variants in disease severity, more so than the single feature analysis. On the other hand, PCA led to the identification of prominent properties involved in the clustering results for variants of different domains.

CONCLUSIONS: The methodology developed here enables the assessment of structural features not available in other prediction tools (e.g., surface distribution of electrostatic potential), evaluating what kind of physicochemical changes are involved in FVIII functional disruption. HCA results allow distinguishing substitutions according to their properties, and yielded clusters which were more homogeneous in phenotype. All evaluated properties are involved in determining disease severity. The nature, as well as the position of the variants in the protein, were shown to be relevant for physicochemical changes, demonstrating that all these aspects must be collectively considered to fine-tune an approach to predict HA severity.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:219

Enthalten in:

Computer methods and programs in biomedicine - 219(2022) vom: 10. Juni, Seite 106768

Sprache:

Englisch

Beteiligte Personen:

Meireles, Mariana R [VerfasserIn]
Stelmach, Lara H [VerfasserIn]
Bandinelli, Eliane [VerfasserIn]
Vieira, Gustavo F [VerfasserIn]

Links:

Volltext

Themen:

839MOZ74GK
9001-27-8
Bioinformatics
Coagulation
F8 protein, human
Factor VIII
Functional impact
Journal Article
Mendelian disorders
Missense mutation
Molecular properties

Anmerkungen:

Date Completed 10.05.2022

Date Revised 31.05.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.cmpb.2022.106768

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM33897802X