Using interpretative phenomenological analysis to gain a qualitative understanding of presence in virtual reality.

Quantitative methods have thus far been the predominant methodological stance of virtual presence research, leaving much to be desired in terms of qualitative understanding. Yet, virtual experiences are a highly personal engagement, unique to each individual, and their presence in virtual reality can be viewed in terms of its experiential individuality. This aspect of the virtual experience is overlooked by conventional quantitative methods, which clusters ratings or scores to form group deductions.

IKK alpha regulates estrogen-induced cell cycle progression by modulating E2F1 expression.

The IkappaB kinase (IKK) complex consists of the catalytic subunits IKKalpha and IKKbeta and a regulatory subunit, IKKgamma/NEMO. Even though IKKalpha and IKKbeta share significant sequence similarity, they have distinct biological roles. It has been demonstrated that IKKs are involved in regulating the proliferation of both normal and tumor cells, although the mechanisms by which they function in this process remain to be better defined.

Structural elements of the tRNA TPsiC loop critical for nucleocytoplasmic transport are important for human immunodeficiency virus type 1 primer selection.

Human immunodeficiency virus type 1 (HIV-1) selects a host cell tRNA as the primer for the initiation of reverse transcription. In a previous study, transport of the intact tRNA from the nucleus to the cytoplasm during tRNA biogenesis was shown to be a requirement for the selection of the tRNA primer by HIV-1. To further examine the importance of tRNA structure for transport and the selection of the primer, yeast tRNA(Phe) mutants were designed such that the native tRNA structure would be disrupted to various extents.

HIV type 1 that select tRNA(His) or tRNA(Lys1,2) as primers for reverse transcription exhibit different infectivities in peripheral blood mononuclear cells.

The replication in human peripheral blood mononuclear cells (PBMC) of unique HIV-1 that select tRNA(His) or tRNA(Lys1,2) for reverse transcription was compared to the wild-type virus that uses tRNA(Lys,3). HIV-1 with only the primer-binding site (PBS) changed to be complementary to these alternative tRNAs initially replicated more slowly than the wild-type virus in PBMC, although all viruses eventually reached equivalent growth as measured by p24 antigen. Viruses with only a PBS complementary to the 3' terminal 18 nucleotides of tRNA(His) or tRNA(Lys1,2) reverted to use tRNA(Lys3).

Yeast tRNA(Phe) expressed in human cells can be selected by HIV-1 for use as a reverse transcription primer.

All naturally occurring human immune deficiency viruses (HIV-1) select and use tRNA(Lys,3) as the primer for reverse transcription. Studies to elucidate the mechanism of tRNA selection from the intracellular milieu have been hampered due to the difficulties in manipulating the endogenous levels of tRNA(Lys,3). We have previously described a mutant HIV-1 with a primer binding site (PBS) complementary to yeast tRNA(Phe) (psHIV-Phe) that relies on transfection of yeast tRNA(Phe) for infectivity.

Probing the importance of tRNA anticodon: human immunodeficiency virus type 1 (HIV-1) RNA genome complementarity with an HIV-1 that selects tRNA(Glu) for replication.

The initiation of human immunodeficiency virus type 1 (HIV-1) reverse transcription occurs at the primer binding site (PBS) that is complementary to the 3'-terminal nucleotides of tRNA(3)(Lys). Why all known strains of HIV-1 select tRNA(3)(Lys) for replication is unknown. Previous studies on the effect of altering the PBS of HIV-1 on replication identified an HIV-1 with a PBS complementary to tRNA(Glu).

Selection of retroviral reverse transcription primer is coordinated with tRNA biogenesis.

Initiation of retrovirus reverse transcription requires the selection of a tRNA primer from the intracellular milieu. To investigate the features of primer selection, a human immunodeficiency virus type 1 (HIV-1) and a murine leukemia virus (MuLV) were created that require yeast tRNA(Phe) to be supplied in trans for infectivity. Wild-type yeast tRNA(Phe) expressed in mammalian cells was transported to the cytoplasm and aminoacylated.