HSV-1 Latency LATs
Category: Virology
from David C. Bloom and Dacia L. Kwiatkowski writing in Alphaherpesviruses: Molecular Virology:
Herpes simplex virus type 1 (HSV-1) latency is characterized by the persistence of viral genomes as episomes in the nuclei of sensory neurons. During this period only one region of the genome is abundantly transcribed: the region encoding the latency-associated transcripts (LATs). The LAT domain is transcriptionally complex, and while the predominant species that accumulates during latency is a 2.0 kb stable intron, other RNA species are transcribed from this region of the genome, including a number of lytic or acute-phase transcripts. In addition, a number of microRNA (miRNA) and non-miRNA small RNAs have recently been mapped to the LAT region of the genome. HSV-1 recombinant viruses with deletions of the LAT promoter exhibit reactivation deficits in a number of animal models, and there is evidence that other LAT deletion mutants also possess altered establishment and virulence properties. The phenotypic complexity associated with this region, as well as evidence that the LATs may play a role in suppressing latent gene expression, suggests that the LAT locus may function as a regulator to modulate the transcription of key lytic and latent genes.
Further reading: Alphaherpesviruses: Molecular Virology
Herpes simplex virus type 1 (HSV-1) latency is characterized by the persistence of viral genomes as episomes in the nuclei of sensory neurons. During this period only one region of the genome is abundantly transcribed: the region encoding the latency-associated transcripts (LATs). The LAT domain is transcriptionally complex, and while the predominant species that accumulates during latency is a 2.0 kb stable intron, other RNA species are transcribed from this region of the genome, including a number of lytic or acute-phase transcripts. In addition, a number of microRNA (miRNA) and non-miRNA small RNAs have recently been mapped to the LAT region of the genome. HSV-1 recombinant viruses with deletions of the LAT promoter exhibit reactivation deficits in a number of animal models, and there is evidence that other LAT deletion mutants also possess altered establishment and virulence properties. The phenotypic complexity associated with this region, as well as evidence that the LATs may play a role in suppressing latent gene expression, suggests that the LAT locus may function as a regulator to modulate the transcription of key lytic and latent genes.
Further reading: Alphaherpesviruses: Molecular Virology
MicroRNAs as Regulators of Host-virus Interactions
from Sassan Asgari and Christopher S. Sullivan in Insect Virology
MicroRNAs (miRNAs) are small non-coding RNA molecules that play a central role in the regulation of gene expression impacting many biological processes. These include development, cancer, apoptosis, immunity, and longevity. In addition, accumulating evidence suggest that miRNAs are likely to be involved in host-virus interactions by modulating expression levels of either defence genes or virus genes. Several groups of animal viruses, as well as insect viruses, encode miRNAs that are instrumental in virus biology, including replication, pathogenesis and latency. Of interest is the biogenesis of miRNAs, current approaches to the discovery of miRNAs, their mode of action and strategies for determining viral miRNA function.
Further reading: Insect Virology
MicroRNAs (miRNAs) are small non-coding RNA molecules that play a central role in the regulation of gene expression impacting many biological processes. These include development, cancer, apoptosis, immunity, and longevity. In addition, accumulating evidence suggest that miRNAs are likely to be involved in host-virus interactions by modulating expression levels of either defence genes or virus genes. Several groups of animal viruses, as well as insect viruses, encode miRNAs that are instrumental in virus biology, including replication, pathogenesis and latency. Of interest is the biogenesis of miRNAs, current approaches to the discovery of miRNAs, their mode of action and strategies for determining viral miRNA function.
Further reading: Insect Virology