Toscana virus NSs protein promotes degradation of double-stranded RNA-dependent protein kinase.
AuthorsKalveram B, Ikegami T,
JournalJ Virol
PubMed ID23325696
'Toscana virus (TOSV), which is transmitted by Phlebotomus spp. sandflies, is a major etiologic agent of aseptic meningitis and encephalitis in the Mediterranean. Like other members of the genus Phlebovirus of the family Bunyaviridae, TOSV encodes a nonstructural protein (NSs) in its small RNA segment. Although the NSs of Rift ... More
APC/C-CCS52A complexes control meristem maintenance in the Arabidopsis root.
AuthorsVanstraelen M, Baloban M, Da Ines O, Cultrone A, Lammens T, Boudolf V, Brown SC, De Veylder L, Mergaert P, Kondorosi E,
JournalProc Natl Acad Sci U S A
PubMed ID19553203
'Plant organs originate from meristems where stem cells are maintained to produce continuously daughter cells that are the source of different cell types. The cell cycle switch gene CCS52A, a substrate specific activator of the anaphase promoting complex/cyclosome (APC/C), controls the mitotic arrest and the transition of mitotic cycles to ... More
DNA replication occurs in all lamina positive micronuclei, but never in lamina negative micronuclei.
AuthorsOkamoto A, Utani K, Shimizu N,
JournalMutagenesis
PubMed ID22086909
A micronucleus is a small nucleus-like structure found in the cytoplasm of dividing cells that suffered from genotoxic stress. It is generally hypothesised that micronuclei content is eventually lost from cells, though the mechanism of how this occurs is unknown. If DNA located within the micronucleus is not replicated, it ... More
NSs protein of rift valley fever virus promotes posttranslational downregulation of the TFIIH subunit p62.
AuthorsKalveram B, Lihoradova O, Ikegami T,
JournalJ Virol
PubMed ID21543505
Rift Valley fever virus (RVFV; family Bunyaviridae, genus Phlebovirus) is an important emerging pathogen of humans and ruminants. Its NSs protein has previously been identified as a major virulence factor that suppresses host defense through three distinct mechanisms: it directly inhibits beta interferon (IFN-ß) promoter activity, it promotes the degradation ... More
CD4 and CD8 T cell immune activation during chronic HIV infection: roles of homeostasis, HIV, type I IFN, and IL-7.
AuthorsCatalfamo M, Wilhelm C, Tcheung L, Proschan M, Friesen T, Park JH, Adelsberger J, Baseler M, Maldarelli F, Davey R, Roby G, Rehm C, Lane C,
JournalJ Immunol
PubMed ID21257970
Immune activation plays an important role in the pathogenesis of HIV disease. Although the causes are not fully understood, the forces that lead to immune dysfunction differ for CD4 and CD8 T cells. In this study, we report that the molecular pathways that drive immune activation during chronic HIV infection ... More
Tim-Tipin dysfunction creates an indispensible reliance on the ATR-Chk1 pathway for continued DNA synthesis.
AuthorsSmith KD, Fu MA, Brown EJ,
JournalJ Cell Biol
PubMed ID19805627
The Tim (Timeless)-Tipin complex has been proposed to maintain genome stability by facilitating ATR-mediated Chk1 activation. However, as a replisome component, Tim-Tipin has also been suggested to couple DNA unwinding to synthesis, an activity expected to suppress single-stranded DNA (ssDNA) accumulation and limit ATR-Chk1 pathway engagement. We now demonstrate that ... More
Dendritic cell-nerve clusters are sites of T cell proliferation in allergic airway inflammation.
AuthorsVeres TZ, Shevchenko M, Krasteva G, Spies E, Prenzler F, Rochlitzer S, Tschernig T, Krug N, Kummer W, Braun A,
JournalAm J Pathol
PubMed ID19179611
Interactions between T cells and dendritic cells in the airway mucosa precede secondary immune responses to inhaled antigen. The purpose of this study was to identify the anatomical locations where dendritic cell-T cell interactions occur, resulting in T cells activation by dendritic cells. In a mouse model of allergic airway ... More
Distinct populations of quiescent and proliferative pancreatic beta-cells identified by HOTcre mediated labeling.
AuthorsHesselson D, Anderson RM, Beinat M, Stainier DY,
JournalProc Natl Acad Sci U S A
PubMed ID19706417
Pancreatic beta-cells are critical regulators of glucose homeostasis, and they vary dramatically in their glucose stimulated metabolic response and levels of insulin secretion. It is unclear whether these parameters are influenced by the developmental origin of individual beta-cells. Using HOTcre, a Cre-based genetic switch that uses heat-induction to precisely control ... More
Large T antigen promotes JC virus replication in G2-arrested cells by inducing ATM- and ATR-mediated G2 checkpoint signaling.
AuthorsOrba Y, Suzuki T, Makino Y, Kubota K, Tanaka S, Kimura T, Sawa H,
JournalJ Biol Chem
PubMed ID19903823
Large T antigen (TAg) of the human polyomavirus JC virus (JCV) possesses DNA binding and helicase activities, which, together with various cellular proteins, are required for replication of the viral genome. We now show that JCV-infected cells expressing TAg accumulate in the G(2) phase of the cell cycle as a ... More