A Single Adaptive Mutation in Sodium Taurocholate Cotransporting Polypeptide Induced by Hepadnaviruses Determines Virus Species-specificity

Abstract

24Hepatitis B virus (HBV) and its hepadnavirus relatives infect a wide range of vertebrates from 25 fish to human. Hepadnaviruses and their hosts have a long history of acquiring adaptive mutations. 26However, there are no reports providing direct molecular evidence for such a coevolutionary "arms 27 race" between hepadnaviruses and their hosts. Here, we present evidence suggesting the adaptive 28 evolution of the sodium taurocholate cotransporting polypeptide (NTCP), an HBV receptor, has been 29 influenced by virus infection. Evolutionary analysis of the NTCP-encoding genes from 20 mammals 30 showed that most NTCP residues are highly conserved among species, exhibiting evolution under 31 negative selection (dN/dS < 1); this observation implies that the evolution of NTCP is restricted by 32 maintaining its original protein function. However, 0.7 % of NTCP amino acid (aa) residues exhibit 33 rapid evolution under positive selection (dN/dS > 1). Notably, a substitution at aa 158, a positively 34 selected residue, converting the human NTCP to a monkey-type sequence abrogated the capacity to 35 support HBV infection; conversely, a substitution at this residue converting the monkey Ntcp to the 36 human sequence was sufficient to confer HBV susceptibility. Together, these observations suggested 37 that positive selection at aa 158 was induced by virus infection. Moreover, the aa 158 sequence 38 determined attachment of the HBV envelope protein to host cell, demonstrating the mechanism 39 whereby HBV infection would create positive selection at this residue in NTCP. In summary, we 40 provide the first evidence in agreement with the function of hepadnavirus as a driver for inducing an 41 adaptive mutation in host receptor. 42 3 Importance 43 Hepatitis B virus (HBV) and its hepadnavirus relatives infect a wide range of vertebrates, with 44 a long infectious history (hundreds of millions of years). Such a long history generally allows adaptive 45 mutations in hosts to escape from infection, while simultaneously allowing adaptive mutations in 46 viruses to overcome host barriers. However, there is no published molecular evidence for such a 47 coevolutionary "arms race" between hepadnaviruses and hosts. In the present study, we performed 48 coevolutionary phylogenetic analysis between hepadnaviruses and the sodium taurocholate 49 cotransporting polypeptide (NTCP), an HBV receptor, combined with virological experimental assays 50 for investigating the biological significance of NTCP sequence variation. Our data provide the first 51 molecular evidences supporting that HBV-related hepadnaviruses drive adaptive evolution in the 52 NTCP sequence, including a mechanistic explanation of how NTCP mutations determine host viral 53 susceptibility. Our novel insights enhance our understanding of how hepadnaviruses evolved with 54 their hosts, permitting the acquisition of strong species-specificity. 55 56 57 4

The NTCP p.Ser267Phe Variant Is Associated With a Faster Anti-HBV Effect on First-Line Nucleos(t)ide Analog Treatment

“…At approximately week 48 or 96, of the presence or absence abnormal NTCP does not play an important role any longer. Second, HBV may evolve sophisticated means to evade or directly counteract the entry restriction factor NTCP and replication inhibitor NAs as a consequence of the continuous interaction with wild-type or mutant NTCP and NAs ( Kluge et al, 2015 ; Jacquet et al, 2019 ; Takeuchi et al, 2019 ). Using phylogenetic analyses, Jacquet et al, (2019) even found that NTCP has been under recurrent positive selection during primate evolution, suggesting that one hallmark of pathogenic virus-host relationships is the reciprocal evolution of host receptors and viral envelope proteins as a result of their antagonistic interaction over time.…”