Exposure to ionizing radiation (IR) during procedures such as abdominal and pelvic radiotherapy results in severe intestinal injury. In the current study, we demonstrated that a lethal dose of IR triggered epithelial cell apoptosis pyroptosis via Caspase-3 cleavage. The ginseng active ingredients, ginsenosides (GS) phenolic acids (GPA), significantly inhibited IR-induced IEC-6 cells. GS GPA als...

Although mitochondrial gene rearrangement has been observed in many insect lineages, little is known about how it affects transcription. To address this question, we first constructed a quantitative transcription map for Aphidius gifuensis, species of parasitoid wasp to have highly rearranged genome (mitogenome) and two potential control regions (CRs). Based on map, assessed the models post-tra...

Two to 10 /ig/ml cytochalasin B (CB) caused retraction of the first cleavage furrow in Triturus eggs, a spreading of the unpigmented surface from the furrow region and a flattening of the whole egg. CB appears to act against the contractility of the microfilamentous band at mid-cleavage so as to relax the furrow and also to weaken unpigmented surface to allow the egg to flatten. Uncleaved eggs ...

Manganese (Mn(2+)) promotes specific cleavage at two major (I and III) and four minor (II, IV, V and VI) sites, in addition to slow non-specific cleavage, in a 659-nucleotide RNA containing the Cr.LSU group I intron. The specific cleavages occurred between G and AAA sequences and thus can be considered Mn(2+)-GAAA ribozymes. We have estimated rates of specific and non-specific cleavages under d...

In the Drosophila and mammalian RNA interference (RNAi) pathways, target RNA destruction is catalyzed by the siRNA-guided, RNA-induced silencing complex (RISC). RISC has been proposed to be an siRNA-directed endonuclease, catalyzing cleavage of a single phosphodiester bond on the RNA target. Although 5' cleavage products are readily detected for RNAi in vitro, only 3' cleavage products have bee...

We have reported previously that Short Interspersed Degenerate Retroposons of the SIDER2 subfamily, largely located within 3'UTRs of Leishmania transcripts, promote rapid turnover of mRNAs through endonucleolytic cleavage within the highly conserved second tandem 79-nt hallmark sequence (79-nt SII). Here, we used site-directed mutagenesis and in silico RNA structural studies to delineate the ci...

The relative increase in Aβ42 peptides from familial Alzheimer disease (FAD) linked APP and PSEN mutations can be related to changes in both ε-cleavage site utilization and subsequent step-wise cleavage. Cleavage at the ε-site releases the amyloid precursor protein (APP) intracellular domain (AICD), and perturbations in the position of ε-cleavage are closely associated with changes in the profi...

There has been much effort directed in recent years towards the design of catalysts for the cleavage of RNA, and the development of an understanding of the mechanism for the cleavage reaction. There has been significant progress in both areas. However, the rate accelerations reported to date for synthetic catalysts of RNA cleavage are, in general, far below those obtained for enzyme catalysts; ...

We investigate the final stage of cytokinesis in two types of amoeba, pointing out the existence of biphasic furrow contraction. The first phase is characterized by a constant contraction rate, is better studied, and seems universal to a large extent. The second phase is more diverse. In Dictyostelium discoideum the transition involves a change in the rate of contraction, and occurs when the wi...