However, Delta IDR1 virus harbored substantially less sigma 1 on

However, Delta IDR1 virus harbored substantially less sigma 1 on the outer capsid. Taken together, these data suggest that sigma 1 length is required for reovirus binding to cells. In contrast, IDR1 is required for stable sigma 1 encapsidation, and IDR2 is required for a postuncoating replication step. Thus, the structural architecture of sigma 1 is required for efficient reovirus infection of host cells.”
“In connection with dyslexia several authors have sought to employ stimuli of very high temporal frequency to isolate magnocellular contributions to visual tasks. It is here pointed out that considerable evidence indicate that the ability to see the very highest temporal frequencies is limited by cortical mechanisms. This suggests that variations and abnormalities in this ability may reflect cortical factors rather than magnocellular ones. It is therefore difficult to rely upon very high temporal frequency stimuli to isolate contributions from the magnocellular

system. (C) 2013 Elsevier Ltd. All rights reserved.”
“We have exploited the ability of transmembrane domains to engage in highly specific protein-protein interactions to construct a new class of small proteins that inhibit HIV infection. By screening a library MLN0128 in vivo encoding hundreds of thousands of artificial transmembrane proteins with randomized transmembrane domains (termed “”traptamers,”" for transmembrane aptamers), we isolated six 44- or 45-amino-acid proteins with completely different transmembrane sequences that inhibited cell surface and total expression of the HIV coreceptor CCR5. The traptamers inhibited transduction of human T cells by HIV reporter viruses pseudotyped with R5-tropic gp120 envelope proteins but had minimal effects on reporter viruses with X4-tropic gp120. Optimization of two traptamers significantly increased their activity and resulted in greater than 95% inhibition of R5-tropic reporter virus transduction without inhibiting expression of CD4, the primary HIV receptor, or CXCR4, another HIV coreceptor. In addition,

traptamers inhibited transduction mediated by a mutant R5-tropic gp120 protein resistant to maraviroc, a small-molecule CCR5 inhibitor, and they dramatically inhibited PCI-32765 molecular weight replication of an R5-tropic laboratory strain of HIV in a multicycle infection assay. Genetic experiments suggested that the active traptamers specifically interacted with the transmembrane domains of CCR5 and that some of the traptamers interacted with different portions of CCR5. Thus, we have constructed multiple proteins not found in nature that interfere with CCR5 expression and inhibit HIV infection. These proteins may be valuable tools to probe the organization of the transmembrane domains of CCR5 and their relationship to its biological activities, and they may serve as starting points to develop new strategies to inhibit HIV infection.

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