ABSTRACT
Oxygen is an essential element for life, which is mostly consumed at mitochondria for energy metabolism. For the genome inside nucleus, oxygen conducts structural regulations and chemical modifications through multiple pathways, where reactive oxygen species (ROS) serve as important messenger molecules. The highly activated ROS have the ability to produce different kinds of DNA lesions, while ferrous ions provide supports in many forms. Under the combinatorial action of oxygen and iron, almost all the genomic biochemical processes, such as replication, transcription and DNA damage repair are affected. Moreover, the variation of environmental oxygen concentration, particularly hypoxia that presents in many major diseases and critical physiological stages, provokes the responds at the genomic level. While the factors that lead to these genomic alterations are potential drug targets and deserve systematic investigations, herein, we collect the existing knowledge in the effects of ROS, ferrous ion and cell hypoxia on genome, along with brief discussions of the related drug molecules.
ABSTRACT
Dicistroviruses comprise a newly characterized and rapidly expanding family of small RNA viruses of invertebrates. Several features of this virus group have attracted considerable research interest in recent years. In this review I provide an overview of the Dicistroviridae and describe progress made toward the understanding and practical application of dicistroviruses, including (i) construction of the first infectious clone of a dicistrovirus, (ii) use of the baculovirus expression system for production of an infectious dicistrovirus, (iii) the use of Drosophila C virus for analysis of host response to virus infection, and (iv) correlation of the presence of Israeli acute paralysis virus with honey bee colony collapse disorder. The potential use of dicistroviruses for insect pest management is also discussed. The structure, mechanism and practical use of the internal ribosome entry site (IRES) elements has recently been reviewed elsewhere.
ABSTRACT
We have cloned a alpha-COP homolog, ancop, from Aspergillus nidulans by colony hybridization of chromosome specific library using alpha-COP homologous fragment as a probe. The probe DNA was amplified with degenerated primers designed by comparison of conserved region of the amino acid sequences of Saccharomyces cerevisiae alpha-COP, Homo sapiens HEP-COP, and Drosophila melanogaster alpha-COP. Full length cDNA clone was also amplified by RT-PCR. Comparison of genomic DNA sequence with cDNA sequence obtained by RT-PCR revealed 7 introns. Amino acid sequence similarity search of the anCop with other alpha-COPs gave an overall identity of 52% with S. cerevisiae, 47% with human and bovine, 45% with Drosophila and Arabidopsis . In upstream region from the transcription start site, a putative TATA and CAAT motif were also identified.