By utilizing a homologous transient expression system, we have demonstrated that the Opaque-2 (O2) gene product O2 confers positive trans-regulation on a 22-kD zein promoter. This trans-acting function of the O2 protein is mediated by its sequence-specific binding to a cis element (the O2 target site) present in the 22-kD zein promoter. A multimer of a 32-bp promoter fragment containing this O2...

BACKGROUND It has been suggested that oxygen (O2) diffusion could be favored in water enriched in O2 by a new electrolytic process because of O2 trapping in water superstructures (clathrates), which could reduce the local pressure/content relationships for O2 and facilitate O2 diffusion along PO2 gradients. MATERIALS AND METHODS Mitochondrial respiration was compared in situ in saponin-skinne...

Respiration rate has been used as an indicator of metabolic rate and associated cost of transport (COT) of free-ranging cetaceans, discounting potential respiration-by-respiration variation in O2 uptake. To investigate the influence of respiration timing on O2 uptake, we developed a dynamic model of O2 exchange and storage. Individual respiration events were revealed from kinematic data from 10...

The Opaque2 (O2) basic leucine (Leu)-zipper transcriptional activator controls the expression of several genes in maize (Zea mays). We investigated the phosphorylation extent of wild-type O2 and mutant-defective or mutant-truncated o2 polypeptides in endosperm cells, their subcellular localization, participation in complex formation, and involvement in functional activity. Besides wild type, fo...

The most frequent and expensive cause category of compensable loss is manual material handling (MMH). Casting workers who handle oxygen (O2) cylinders manually are at risk for work-related musculoskeletal disorders (WMSDs). The aim of this study was to assess manual handling of O2 cylinders by casting workers and to implement ergonomic intervention to reduce the risk of musculoskeletal disorder...

In this study, the structures, the IR spectroscopy, and the electronic properties of AunCum (n+m≤5) bimetallic clusters were studied and compared with those of pure gold and copper clusters using the generalized gradient approximation (GGA) and exchange correlation density functional theory (DFT). The study of an O2-AunCum system is important to identify the promotion effects of each of the two...

Protein targeting to the nucleus has been studied extensively in animal and yeast systems; however, nothing is known about nuclear targeting in plants. The Opaque-2 (O2) gene produces a regulatory protein that is responsible for inducing transcription of the alpha-zein class of storage proteins in maize kernels. The cloned O2 gene encodes a protein that contains a leucine zipper DNA binding dom...

Cells devoid of cytosolic superoxide dismutase (SOD) suffer enzyme inactivation, growth deficiencies, and DNA damage. It has been proposed that the scant superoxide (O2-) generated by aerobic metabolism harms even cells that contain abundant SOD. However, this idea has been difficult to test. To determine the amount of O2- that is needed to cause these defects, we modulated the O2- concentratio...

BACKGROUND AND OBJECTIVES Since resuscitators with self-inflating bag-mask systems manufactured and/or commercialized in Brazil are widely available and used in health services, both out- and intra-hospitals, the objective of this study was to determine the O2 fractions delivered by seven resuscitators receiving different O2 flows. METHODS Seven resuscitators with self-inflating bag-mask syst...