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Basic Characteristics of Mutations
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Mutation Site
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P142A |
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Mutation Site Sentence
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Such lesions consisted in a small deletion (Δ119-123) or single amino acid substitutions (I110A, P120A, R122A, C139S, K141A, P142A, C147S, C149S, I150A, P153A, and W156A), which have been described previously as drastically reducing HDV infectivity when present in all three S-, M-, and L-HBsAg proteins (2, 39). |
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Mutation Level
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Amino acid level |
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Mutation Type
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Nonsynonymous substitution |
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Gene/Protein/Region
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S |
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Standardized Encoding Gene
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S
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Genotype/Subtype
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- |
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Viral Reference
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-
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Functional Impact and Mechanisms
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Disease
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Hepatitis B Virus Infection
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Immune
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Y |
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Target Gene
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-
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Clinical and Epidemiological Correlations
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Clinical Information
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- |
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Treatment
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- |
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Location
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- |
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Literature Information
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PMID
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19759159
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Title
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The pre-S1 and antigenic loop infectivity determinants of the hepatitis B virus envelope proteins are functionally independent
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Author
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Le Duff Y,Blanchet M,Sureau C
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Journal
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Journal of virology
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Journal Info
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2009 Dec;83(23):12443-51
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Abstract
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The hepatitis B virus (HBV) envelope proteins bear two determinants of viral entry: a receptor-binding site (RBS) in the pre-S1 domain of the large envelope protein and a conformation-dependent determinant, of unknown function, in the antigenic loop (AGL) of the small, middle, and large envelope proteins. Using an in vitro infection assay consisting of susceptible HepaRG cells and the hepatitis delta virus (HDV) as a surrogate of HBV, we first investigated whether subelements of the pre-S1 determinant (amino acids 2 to 75), i.e., the N-terminal myristoyl anchor, subdomain 2-48 (RBS), and subdomain 49-75, were functionally separable. In transcomplementation experiments, coexpression of two distinct infectivity-deficient pre-S1 mutants at the surface of HDV virions failed to restore infectivity, indicating that the myristoyl anchor, the 2-48 RBS, and the 49-75 sequence, likely cooperate in cis at viral entry. Furthermore, we showed that as much as 52% of total pre-S1 in the HDV envelope could bear infectivity-deficient lesions without affecting entry, indicating that a small number of pre-S1 polypeptides-estimated at three to four per virion-is sufficient for infectivity. We next investigated the AGL activity in the small or large envelope protein background (S- and L-AGL, respectively) and found that lesions in S-AGL were more deleterious to infectivity than in L-AGL, a difference that reflects the relative stoichiometry of the small and large envelope proteins in the viral envelope. Finally, we showed that C147S, an AGL infectivity-deficient substitution, exerted a dominant-negative effect on infectivity, likely reflecting an involvement of C147 in intermolecular disulfide bonds.
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Sequence Data
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-
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