Molecular cloning and expression analysis of Fshr and Lhr in relation to Fshb and Lhb subunits during the period of temperature‐dependent sex determination in pejerrey Odontesthes bonariensis

In this study, we cloned and characterized the follicle stimulating hormone receptor (Fshr) and luteinizing hormone receptor (Lhr) cDNAs of pejerrey Odontesthes bonariensis, a species with temperature‐dependent sex determination (TSD), and analyzed their expression in relation to Fshb and Lhb subunits during gonadogenesis at temperatures producing only females (17°C, FPT), both sexes (25°C, MixPT), and only males (29°C, MPT). The pejerrey Fshr cDNA had 3,069 bp for a mature protein of 694 amino acids (aa) and a signal peptide of 22 aa; the Lhr cDNA had 2,936 bp for a mature protein of 676 aa and a signal peptide of 25 aa. With the exception of Lhr in fish at the MPT, all genes showed significant increases and/or peaks of expression before histological differentiation of the gonads regardless of temperature. Larvae at the FPT had lower Fshb and Lhb but higher Lhr expression during the TSD period than those at the MPT; a clear pattern could not be ascertained for Fshr. At the MixPT, Fshb, Lhb, and Lhr mRNA increased in approximately half of the fish during TSD and sex differentiation and the sex ratio was 55.2% male. Based on the above results, it is suggested that animals with high Fshb and Lhb and low Lhr values represent putative males. These evidences, together with other studies, suggest that temperature may signal through the pituitary (differential expression of Fshb and Lhb) down to the gonads (differential expression of Lhr), probably affecting the regulation of steroidogenesis during the TSD process of pejerrey. Mol. Reprod. Dev. 77: 521–532, 2010. © 2010 Wiley‐Liss, Inc.     

Novel metabolic pathway for salicylate biodegradation via phenol in yeast <Emphasis Type="Italic">Trichosporon moniliiforme</Emphasis>

A novel metabolic pathway was found in the yeast Trichosporon moniliiforme WU-0401 for salicylate degradation via phenol as the key intermediate. When 20 mM salicylate was used as the sole carbon source for the growth of strain WU-0401, phenol was detected as a distinct metabolite in the culture broth. Analysis of the products derived from salicylate or phenol through reactions with resting cells and a cell-free extract of strain WU-0401 indicated that salicylate is initially decarboxylated to phenol and then oxidized to catechol, followed by aromatic ring cleavage to form cis-cis muconate.     

A single oral administration of acetic acid increased energy expenditure in C57BL/6J mice

We have reported that acetic acid (AcOH) intake suppresses body fat mass and up-regulates the genes involved in fatty acid oxidation, but it is not clear whether the suppression of body fat mass by AcOH administration is due to an increase in energy expenditure (EE). In this study, we investigated to determine whether a single oral administration of AcOH would increase EE in C57BL/6J mice treated with 1.5% AcOH. The AcOH treatment group had significantly higher oxygen consumption (VO(2)), EE, and fat oxidation (FAT) than the water treatment group. These results suggest that a single administration of AcOH increases EE, resulting in suppression of body fat mass.     

Capillary electrophoresis of chitooligosaccharides in acidic solution: Simple determination using a quaternary-ammonium-modified column and indirect photometric detection with Crystal Violet

Five chitosan oligosaccharides were separated in acidic aqueous solution by capillary electrophoresis (CE) with indirect photometric detection using a positively coated capillary. Electrophoretic mobility of the chitooligosaccharides (COSs) depended on the number of monomer units in acidic aqueous solution, similar to other polyelectrolyte oligomers. The separation was developed in nitric acid aqueous solution at pH 3.0 with 1 mM Crystal Violet, using a capillary positively coated with N-trimethoxypropyl-N,N,N-trimethylammonium chloride. The limit of the detection for chitooligosaccharides with two to six saccharide chains was less than 5 μM. CE determination of an enzymatically hydrolyzed COS agreed with results from HPLC.     

Purification and properties of 3 alpha-hydroxyglycyrrhetinate dehydrogenase of Clostridium innocuum from human intestine

3 alpha-Hydroxyglycyrrhetinate dehydrogenase of Clostridium innocuum, isolated from human intestinal bacteria, was capable of converting 3-ketoglycyrrhetic acid to 3 alpha-hydroxyglycyrrhetic acid. The enzyme was purified to homogeneity by means of butyl-Toyopearl 650M, Sephadex G-150, Matrex Red A, Toyopearl HW-55S, and isoelectric focusing column chromatographies. The purified enzyme showed a specific activity of 156 mumol/min.mg toward 3 alpha-hydroxyglycyrrhetic acid, and showed a single band on SDS-polyacrylamide gel electrophoresis. The apparent molecular weight was 53,000, as estimated by gel filtration, and 30,000, as judged by SDS-polyacrylamide gel electrophoresis. Its isoelectric point was 5.2. The enzyme showed absolute specificity for the 3 alpha-hydroxyl and 3-ketonic groups of 18 alpha- or 18 beta-glycyrrhetic acid and required NADP+ and NADPH as cosubstrates. The enzyme did not act on any 3 alpha-hydroxyl or 3-ketonic group of steroids or bile acids. The enzyme is a novel type of enzyme, defined as 3 alpha-hydroxy-glycyrrhetinate dehydrogenase, being quite different from 3 alpha-hydroxysteroid dehydrogenase [EC 1.1.1.50].     

High-resolution spatiotemporal transcriptome analyses during cellularization of rice endosperm unveil the earliest gene regulation critical for aleurone and starchy endosperm cell fate specification

Journal of Plant Research - The major tissues of the cereal endosperm are the starchy endosperm (SE) in the inner and the aleurone layer (AL) at the outer periphery. The fates of the cells that...     

The mitochondrial Ca2+ uptake regulator,MICU1, is involved in cold stress‐induced ferroptosis

Ferroptosis has recently attracted much interest because of its relevance to human diseases such as cancer and ischemia‐reperfusion injury. We have reported that prolonged severe cold stress induces lipid peroxidation‐dependent ferroptosis, but the upstream mechanism remains unknown. Here, using genome‐wide CRISPR screening, we found that a mitochondrial Ca²⁺ uptake regulator, mitochondrial calcium uptake 1 (MICU1), is required for generating lipid peroxide and subsequent ferroptosis under cold stress. Furthermore, the gatekeeping activity of MICU1 through mitochondrial calcium uniporter (MCU) is suggested to be indispensable for cold stress‐induced ferroptosis. MICU1 is required for mitochondrial Ca²⁺ increase, hyperpolarization of the mitochondrial membrane potential (MMP), and subsequent lipid peroxidation under cold stress. Collectively, these findings suggest that the MICU1‐dependent mitochondrial Ca²⁺ homeostasis‐MMP hyperpolarization axis is involved in cold stress‐induced lipid peroxidation and ferroptosis.     

Exercise-induced activation of cardiac sympathetic nerve triggers cardioprotection via redox-sensitive activation of eNOS and upregulation of iNOS

We investigated the mechanism of exercise-induced late cardioprotection against ischemia-reperfusion (I/R) injury. C57BL/6 mice received treadmill exercise (60 min/day) for 7 days at a work rate of 60-70% maximal oxygen uptake. Exercise transiently increased oxidative stress and activated endothelial isoform of nitric oxide synthase (eNOS) during exercise and increased expression of inducible isoform of NOS (iNOS) in the heart after 7 days of exercise. The mice were subjected to regional ischemia by 30 min of occlusion of the left coronary artery, followed by 2 h of reperfusion. Infarct size was significantly smaller in the exercised mice. Ablation of cardiac sympathetic nerve by topical application of phenol abolished oxidative stress, activation of eNOS, upregulation of iNOS, and cardioprotection mediated by exercise. Treatment with the antioxidant N-(2-mercaptopropionyl)-glycine during exercise also inhibited activation of eNOS, upregulation of iNOS, and cardioprotection. In eNOS(-/-) mice, exercise-induced oxidative stress was conserved, but upregulation of iNOS and cardioprotection was lost. Exercise did not confer cardioprotection when the iNOS selective inhibitor 1400W was administered just before coronary artery occlusion or when iNOS(-/-) mice were employed. These results suggest that exercise stimulates cardiac sympathetic nerves that provoke redox-sensitive activation of eNOS, leading to upregulation of iNOS, which acts as a mediator of late cardioprotection against I/R injury.