The mutation G541R within the ectodomain of TM was isolated in three independent chimeric enveloped murine leukemia virus (MuLV) viral populations originally impaired in viral passage and in wild-type 4070A. Isolation of G541R in multiple populations suggested it played a critical role in viral envelope function. Using a viral vector system, the observed effects of the G541R mutation within MuL...

Viral infections involve a complex interplay of the immune response and escape mutation of the virus quasispecies inside a single host. Although fundamental aspects of such a balance of mutation and selection pressure have been established by the quasispecies theory decades ago, its implications have largely remained qualitative. Here, we present a quantitative approach to model the virus evolu...

Evolution at high mutation rates is expected to reduce population fitness deterministically by the accumulation of deleterious mutations. A high enough rate should even cause extinction (lethal mutagenesis), a principle motivating the clinical use of mutagenic drugs to treat viral infections. The impact of a high mutation rate on long-term viral fitness was tested here. A large population of th...

chédiak-higashi syndrome is a rare autosomal recessive congenital immunodeficiency mainly characterized by a condition called oculo-cutaneous albinism. the affected subjects have light-colored hair, vision problems, blood clotting (coagulation) abnormalities and in adulthood varying neurologic disorders. recurrent infections, particularly viral infection with other disorders in childhood are us...

knowledge about the clinical significance of v-raf murine sarcoma viral oncogene homolog b1 ( braf ) mutations in colorectal cancer (crc) is growing. braf encodes a protein kinase involved with intracellular signaling and cell division. the gene product is a downstream effector of kirsten ras 1( kras ) within the ras/raf/mapk cellular signaling pathway. evidence suggests that braf mutations, li...

conclusions although the patients carrying m204i mutation were more likely to show lack of responses to lam therapy, lam replacing by other nucleoside/tide analogs plus hbig maybe still effective in decreasing hepatitis b recurrence after liver transplantation. however, it is suggested that drug resistance test should be considered by clinicians during therapeutic management to avoid the follow...

Resistance of influenza A viruses to neuraminidase inhibitors can arise through mutations in the neuraminidase (NA) gene. We show here that a Q136K mutation in the NA of the 2009 pandemic H1N1 virus confers a high degree of resistance to zanamivir. Resistance is accompanied by reduced numbers of NA molecules in viral particles and reduced intrinsic enzymatic activity of mutant NA. Interestingly...

Clinical outcomes of chronic hepatitis B virus (HBV) infection vary widely. In addition to host factors, several viral factors including HBV genotype, viral load, specific viral mutations and quantitative HBsAg levels, have been associated with disease outcomes. Among viral factors, HBV genotype correlates with not only the clinical outcomes, but also with the response to interferon treatment. ...

Picornaviral RNA replication utilizes a small virus-encoded protein, termed 3B or VPg, as a primer to initiate RNA synthesis. This priming step requires uridylylation of the VPg peptide by the viral polymerase protein 3D(pol), in conjunction with other viral or host cofactors. In this study, we compared the viral specificity in 3D(pol)-catalyzed uridylylation reactions between poliovirus (PV) a...