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Corresponding mRNA (corresponding + mrna)

Distribution by Scientific Domains

Medical Sciences	60%

Selected Abstracts

The expression of glutathione reductase in the male reproductive system of rats supports the enzymatic basis of glutathione function in spermatogenesis

FEBS JOURNAL, Issue 5 2002
Tomoko Kaneko
Glutathione reductase (GR) recycles oxidized glutathione (GSSG) by converting it to the reduced form (GSH) using an NADPH as the electron source. The function of GR in the male genital tract of the rat was examined by measuring its enzymatic activity and examining the gene expression and localization of the protein. Levels of GR activity, the protein, and the corresponding mRNA were the highest in epididymis among testes, vas deferens, seminal vesicle, and prostate gland. The localization of GR, as evidenced by immunohistochemical techniques, reveals that it exists at high levels in the epithelia of the genital tract. In testis, GR is mainly localized in Sertoli cells. The enzymatic activity and protein expression of GR in primary cultured testicular cells confirmed its predominant expression in Sertoli cells. Intracellular GSH levels, expressed as mol per mg protein, was higher in spermatogenic cells than in Sertoli cells. As a result of these findings, the effects of buthionine sulfoximine (BSO), an inhibitor for GSH synthesis, and 1,3-bis(2-chlorethyl)-1-nitrosourea (BCNU), an inhibitor for GR, on cultured testicular cells were examined. Sertoli cells were prone to die as the result of BCNU, but not BSO treatment, although intracellular levels of GSH declined more severely with BSO treatment. Spermatogenic cells were less sensitive to these agents than Sertoli cells, which indicates that the contribution of these enzymes is less significant in spermatogenic cells. The results herein suggest that the GR system in Sertoli cells is involved in the supplementation of GSH to spermatogenic cells in which high levels of cysteine are required for protamine synthesis. In turn, the genital tract, the epithelia of which are rich in GR, functions in an antioxidative manner to protect sulfhydryl groups and unsaturated fatty acids in spermatozoa from oxidation during the maturation process and storage. [source]

Insecticide resistance in the aphid Myzus persicae (Sulzer): chromosome location and epigenetic effects on esterase gene expression in clonal lineages

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2003
LINDA M. FIELD
Insecticide treatment of the aphid Myzus persicae (Sulzer) has led to the evolution of several insecticide resistance mechanisms, including the detoxification of insecticides by elevated esterases. This results from amplification of one of two closely related esterase genes (E4 or FE4) with up to 80 copies in the most resistant aphids. The amplified E4 genes are at a single site linked to a chromosomal translocation and resistance can be unstable. Individuals within a clone lose their elevated esterase and resistant phenotype, a good example of ,clonal variation'. This loss of esterase is accompanied by a loss of the corresponding mRNA but the amplified genes are retained with no detectable sequence differences. However, the expressed E4 genes contain 5-methylcytosine, which is lost at the same time as the genes are turned off. This is in direct contrast with vertebrate genes where DNA methylation causes gene silencing, but it does suggest that the resistant phenotype in M. persicae is under epigenetic control. One hypothesis is that 5-methylcytosine in E4 genes facilitates expression by preventing the production of incorrectly initiated transcripts. It is interesting that we have never detected silencing of amplified FE4 genes, possibly because they are at multiple loci and therefore less likely to be subject to synchronous control. © 2003 The Linnean Society of London. Biological Journal of the Linnean Society, 2003, 79, 107,113. [source]

Adenosine A2A Receptors are Up-regulated in Pick's Disease Frontal Cortex

BRAIN PATHOLOGY, Issue 4 2006
José Luís Albasanz PhD
Adenosine A2A receptors (A2AR) are highly expressed in striatum. However, they are also present in extrastriatal structures. A2AR were studied in post-mortem human frontal cortex from Pick's disease (PiD) and age-matched non-demented controls by radioligand binding assays, Western-blotting, real-time PCR and adenylyl cyclase activity determination. Saturation binding assay using [3H]ZM 241385, a selective A2A antagonist, as radioligand revealed a significant increase in total adenosine A2AR numbers (Bmax) in frontal cortex from PiD samples (191% of control Bmax), suggesting up-regulation of this receptor. A significant increase in the level of A2AR was also detected by Western-blotting. Furthermore, expression of mRNA coding A2AR determined by quantitative real-time PCR was enhanced. In agreement, stimulation of adenylyl cyclase by CGS 21680, a selective A2A receptor agonist, was significantly strengthened. Up-regulation of A2B receptors and their corresponding mRNA was also observed. These results show that A2A adenosine receptor/adenylyl cyclase transduction pathway is up-regulated and sensitized in frontal cortex brain from PiD. [source]

A review of morphological techniques for detection of peroxisomal (and mitochondrial) proteins and their corresponding mRNAs during ontogenesis in mice: Application to the PEX5-knockout mouse with Zellweger syndrome

MICROSCOPY RESEARCH AND TECHNIQUE, Issue 2 2003
Eveline Baumgart
Abstract In the era of application of molecular biological gene-targeting technology for the generation of knockout mouse models to study human genetic diseases, the availability of highly sensitive and reliable methods for the morphological characterization of the specific phenotypes of these mice is of great importance. In the first part of this report, the role of morphological techniques for studying the biology and pathology of peroxisomes is reviewed, and the techniques established in our laboratories for the localization of peroxisomal proteins and corresponding mRNAs in fetal and newborn mice are presented and discussed in the context of the international literature. In the second part, the literature on the ontogenetic development of the peroxisomal compartment in mice, with special emphasis on liver and intestine is reviewed and compared with our own data reported recently. In addition, some recent data on the pathological alterations in the liver of the PEX5,/, mouse with a peroxisomal biogenesis defect are briefly discussed. Finally, the methods developed during these studies for the localization of mitochondrial proteins (respiratory chain complexes and MnSOD) are presented and their advantages and pitfalls discussed. With the help of these techniques, it is now possible to identify and distinguish unequivocally peroxisomes from mitochondria, two classes of cell organelles giving by light microscopy a punctate staining pattern in microscopical immunohistochemical preparations of paraffin-embedded mouse tissues. Microsc. Res. Tech. 61:121,138, 2003. © 2003 Wiley-Liss, Inc. [source]