Regulatory noncoding RNAs and the major histocompatibility complex.

The Major Histocompatibility Complex (MHC) is a 4 Mbp genomic region located on the short arm of chromosome 6. The MHC region contains many key immune-related genes such as Human Leukocyte Antigens (HLAs). There has been a growing realization that, apart from MHC encoded proteins, RNAs derived from noncoding regions of the MHC-specifically microRNAs (miRNAs) and long noncoding RNAs (lncRNAs)-play a significant role in cellular regulation.

miR-211 is a prosurvival microRNA that regulates chop expression in a PERK-dependent manner.

MicroRNAs typically function at the level of posttranscriptional gene silencing within the cytoplasm; however, increasing evidence suggests that they may also function in nuclear, Argonaut-containing complexes, to directly repress target gene transcription. We have investigated the role of microRNAs in mediating endoplasmic reticulum (ER) stress responses. ER stress triggers the activation of three signaling molecules: Ire-1α/β, PERK, and ATF6, whose function is to facilitate adaption to the ensuing stress.

A virion-associated protein kinase induces apoptosis.

Apoptosis and inhibition of host gene expression are often associated with virus infections. Many viral polypeptides modulate apoptosis by direct interaction with highly conserved apoptotic pathways. Some viruses induce apoptosis during late stages of the infection cycle, while others inhibit apoptosis to facilitate replication or maintain persistent infection.

Modulation of iridovirus-induced apoptosis by endocytosis, early expression, JNK, and apical caspase.

Chilo iridescent virus (CIV) is the type species for the family Iridoviridae, which are large, isometric, cytoplasmic dsDNA viruses. We examined the mechanism of apoptosis induction by CIV. High CIV doses (CIV(XS); 400 microg/ml), UV-irradiated virus (CIV(UV); 10 microg/ml) and CVPE (CIV protein extract; 10 microg/ml) induced apoptosis in 60% of treated Choristoneura fumiferana (IPRI-CF-124T) cells.