Molecular basis of P[II] major human rotavirus VP8* domain recognition of histo-blood group antigens

Abstract

Initial cell attachment of rotavirus (RV) to specific cell surface glycan receptors, which is the essential first step in RV infection, is mediated by the VP8* domain of the spike protein VP4. Recently, human histo-blood group antigens (HBGAs) have been identified as receptors or attachment factors for human RV strains. RV strains in the P[4] and P[8] genotypes of the P [II] genogroup share common recognition of the Lewis b (Le b) and H type 1 antigens, however, the molecular basis of receptor recognition by the major human P[8] RVs remains unknown due to lack of experimental structural information. Here, we used nuclear magnetic resonance (NMR) spectroscopy-based titration experiments and NMR-derived high ambiguity driven docking (HADDOCK) methods to elucidate the molecular basis for P[8] VP8* recognition of the Le b (LNDFH I) and type 1 HBGAs. We also used X-ray crystallography to determine the molecular details underlying P[6] recognition of H type 1 HBGAs. Unlike P[6]/ P[19] VP8*s that recognize H type 1 HBGAs in a binding surface composed of an α-helix and a β-sheet, referred as the "βα binding site", the P[8] and P[4] VP8*s bind Le b HBGAs in a previously undescribed pocket formed by the edges of two β-sheets, referred to as the "ββ binding site". Importantly, the P[8] and P[4] VP8*s retain binding capability to non-Le b type 1 HBGAs using the βα binding site. The presence of two distinct binding sites for Le b and non-Le b HBGA glycans in the P[8] and P[4] VP8* domains suggests host-pathogen co-evolution under structural and functional adaptation of RV pathogens to host glycan polymorphisms. Assessment and understanding of the precise impact of this co-evolutionary process in determining RV host ranges and cross-species RV transmission should facilitate improved RV vaccine development and prediction of future RV strain emergence and epidemics.

Histo-blood group antigens as divergent factors of groups A and C rotaviruses circulating in humans and different animal species

“…Interestingly, a trisaccharide glycan Galα1-3Galβ1-4Glc (glycan number 117) containing an αGal was found to be recognised by multiple strains representing one RVC and six RVA genotypes, indicating evolutionary connections among these genotypes with the αGal glycan as a common receptor (Figure 1). Four strains exhibited strongest binding signals to the αGal containing glycans, including two murine RVAs in the P [16] genotype (the prototype murine RV EDIM and a variant murine RV EMcN [22,23]), P [3] genotype in RVA that infects animals and humans, and a bovine strain in a RVC genotype. It is known that the αGal transferase responsible for synthesis of αGal glycan is produced in some animal species, but the gene encoding the specific αGal transferase is inactive in humans [24].…”

“…RVAs representing two P[I] genotypes (P [3] and P [7]) known as sialic acid (SA)-dependent and another two P[I] genotypes known as SA-independent (P [15] and P [23]) [7,25,26] have been found binding SA-glycans at high affinity ( Figure 2). Interestingly, these four SA-binding genotypes are genetically closely related and form a cluster together with other four SA-dependent genotypes (P [1], P [2], P [16] and P [20], excepting P [18], Figure 1 and Table 1) in the RVA P[I] genogroup. These findings indicated a new direction of RV evolution under selection of SA-containing glycans, consistent with the previous finding that many animal RVAs are SA-dependent [6,7].…”

“…These P[II] RVAs were originated from an ancestor with a potential animal host origin in P[I] genogroup that mainly infecting different animals [14,15]. Genetic analyses also revealed a co-evolutionary relationship of P[II] RVs with humans under selection of the stepwisely synthesised H type 1 HBGAs in humans that are developmentally regulated in newborn infants and evolutionarily conserved with some animals ( Figure 5) [8,[14][15][16]. Structural/functional analyses of VP8*of P[II] RVs also elucidated the molecular details of receptor binding property changes in each step of RV co-evolution with humans reflecting the step wise synthesis of HBGAs in humans vs. some animal species, explaining the genotype-specific host ranges, disease burden, epidemiology and vaccine development against RVs [15,16].…”

“…Significant advancements have been made in understanding evolution of major human RVs following step wise adaptations from an animal host origin to humans under selection of strain-specific HBGA glycans, reflecting the step-wisely synthesised HBGAs in humans [8,[14][15][16]. This new knowledge provides valuable information on disease burdens and epidemiology, as well as vaccine development against RVs.…”

FUT2, Secretor Status and FUT3 Polymorphisms of Children with Acute Diarrhea Infected with Rotavirus and Norovirus in Brazil

“…On the other hand, recent structural studies involving P[8] VP8* binding to HBGA presented conflicting results. While some indicate the additional fucose conferred by the Lewis b antigen would cause steric hindrance to the interaction, other studies demonstrated binding of P[8] VP8* to the Lewis b antigen via a pocket formed by two β-sheets [ 63 , 64 , 65 ]. Further studies are warranted to clarify this issue.…”