Studying the Interactions of U24 from HHV-6 in Order to Further Elucidate Its Potential Role in MS

• Published in: Viruses Vol. 14; no. 11; p. 2384
• Main Authors: Pi, Keng-Shuo, Bortolotti, Daria, Sang, Yurou, Schiuma, Giovanna, Beltrami, Silvia, Rizzo, Sabrina, Bortoluzzi, Alessandra, Baldi, Eleonora, Creagh, A Louise, Haynes, Charles A, Rizzo, Roberta, Straus, Suzana K
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 28.10.2022; MDPI
• Subjects: Calorimetry; Cell activation; Ethics; Fyn protein; Fyn-SH3; Genetic aspects; Health aspects; Herpesvirus 6, Human - physiology; human herpes virus; Human herpesvirus 6; Human subjects; Humans; Killer cells; Medical research; Membrane proteins; Multiple Sclerosis; Myelin; Myelin basic protein; Natural killer cells; Nedd4L; NMR; Nuclear magnetic resonance; Nuclear Magnetic Resonance, Biomolecular; Peptides; Phosphorylation; Physiological aspects; Potassium channels (inwardly-rectifying); Proteins; Risk factors; Roseolovirus; Roseolovirus Infections; Titration; Viral infections; Viruses; Canada; United States > US; Roseolovirus; natural killer cells; human herpes virus; multiple sclerosis; Nedd4L; Killer Cell Immunoglobulin Like Receptor 2DL2; phosphorylation; Fyn-SH3
• ISSN: 1999-4915; 1999-4915
• DOI: 10.3390/v14112384

A number of studies have suggested that human herpesvirus 6A (HHV-6A) may play a role in multiple sclerosis (MS). Three possible hypotheses have been investigated: (1) U24 from HHV-6A (U24-6A) mimics myelin basic protein (MBP) through analogous phosphorylation and interaction with Fyn-SH3; (2) U24-6A affects endocytic recycling by binding human neural precursor cell (NPC) expressed developmentally down-regulated protein 4-like WW3* domain (hNedd4L-WW3*); and (3) MS patients who express Killer Cell Immunoglobulin Like Receptor 2DL2 (KIR2DL2) on natural killer (NK) cells are more susceptible to HHV-6 infection. In this contribution, we examined the validity of these propositions by investigating the interactions of U24 from HHV-6B (U24-6B), a variant less commonly linked to MS, with Fyn-SH3 and hNedd4L-WW3* using heteronuclear single quantum coherence (HSQC) nuclear magnetic resonance (NMR) titrations and isothermal titration calorimetry (ITC). In addition, the importance of phosphorylation and the specific role of U24 in NK cell activation in MS patients were examined. Overall, the findings allowed us to shed light into the models linking HHV-6 to MS and the involvement of U24.