Squalene is a natural triterpene and an important intermediate of sterol and hopanoid biosynthesis in various types of cell from bacteria to human. Synthesis and further conversion of squalene are key steps in the metabolism of sterols and related components. Here we summarize the recent knowledge of squalene biochemistry, its molecular properties, and its physiological effects. We compare squalene biosynthetic pathways in different cell types and describe biotechnological strategies to isolate this lipid. Finally, applications of squalene in nutrition, pharmacy, and medicine are discussed.
The exploitation of male sterility systems has enabled the commercialization of heterosis in rice, with greatly increased yield and total production of this major staple food crop. Hybrid rice, which was adopted in the 1970s, now covers nearly 13.6 million hectares each year in China alone. Various types of cytoplasmic male sterility (CMS) and environment-conditioned genic male sterility (EGMS) systems have been applied in hybrid rice production. In this paper, recent advances in genetics, biochemistry, and molecular biology are reviewed with an emphasis on major male sterility systems in rice: five CMS systems, i.e., BT-, HL-, WA-, LD- and CW- CMS, and two EGMS systems, i.e., photoperiod- and temperature-sensitive genic male sterility (P/TGMS). The interaction of chimeric mitochondrial genes with nuclear genes causes CMS, which may be restored by restorer of fertility (Rf) genes. The PGMS, on the other hand, is conditioned by a non-coding RNA gene. A survey of the various CMS and EGMS lines used in hybrid rice production over the past three decades shows that the two-line system utilizing EGMS lines is playing a steadily larger role and TGMS lines predominate the current two-line system for hybrid rice production. The findings and experience gained during development and application of, and research on male sterility in rice not only advanced our understanding but also shed light on applications to other crops.
Diabetes-specific microvascular disease is a leading cause of blindness, renal failure and nerve damage, and diabetes-accelerated atherosclerosis leads to increased risk of myocardial infarction, stroke and limb amputation. Four main molecular mechanisms have been implicated in glucose-mediated vascular damage. All seem to reflect a single hyperglycaemia-induced process of overproduction of superoxide by the mitochondrial electron-transport chain. This integrating paradigm provides a new conceptual framework for future research and drug discovery.
To study the role of cancer stem cells in aggregates, we have isolated clusters and cells from transgenic mice that express Polyoma virus middle-T antigen (MMTV-PyMT) which causes aggressive breast tumors. [...]mys provides a rare opportunity to investigate the origins and evolutionary history of a relatively "young" TE family, providing insights into features that reflect their capabilities in becoming "genomic parasites." Alex Gruber, Kadijah Kalo, Laura Bruton, and Jeffery Morrissette, Lawrence Technological University Zebrafish (Danio rerio) are biological model organisms as they are a predictive model for human diseases and development. Preliminary results suggest that ARPE-19 cells alter stress gene induction in as little as 24 hours after initiating the stressful condition. [...]fluctuating glucose levels have distinct effects relative to high or low glucose concentrations alone.
This study explores interdisciplinarity evolution of Biochemistry and Molecular Biology (BMB) over a one-hundred-year period on several fronts, namely: change in interdisciplinarity, identification of core disciplines, disciplinary emergence, and potential discipline detection, in order to assess the evolution of interdisciplinarity over time. Science overlay maps and a StreamGraph were used to visualize interdisciplinary evolution. Our study confirms that interdisciplinarity evolves mainly from neighbouring fields to distant cognitive areas and provides evidence of an increasing tendency of BMB researchers to cite literature from other disciplines. Additionally, from our results, we can see that the top potential interdisciplinary relations belong to distant disciplines of BMB; their share of references is small, but is increasing markedly. On the whole, these results confirm the dynamic nature of interdisciplinary relations, and suggest that current scientific problems are increasingly addressed using knowledge from a wide variety of disciplines.