Benzo(a)pyrene induced glycine N-methyltransferase messenger RNA expression in Fundulus heteroclitus embryos |
| |
| Institution: | 1. Department of Pharmacology and Environmental Toxicology Research Program, School of Pharmacy, University of Mississippi, University, MS, USA;2. USDA-ARS Genomics and Bioinformatics Research Unit, Stoneville, MS, USA;1. University of Le Havre, Laboratory of Ecotoxicology, 25 Rue Philippe Lebon, BP 540, Le Havre 76058, France;2. Université Bordeaux, 1 CNRS UMR 5255, Batiment A12, 351 Cours de la Libération, 33405 TALENCE Cedex;3. Plymouth Marine Laboratory, Prospect Place, The Hoe, Plymouth, PL 3DH, United Kingdom;4. Applied Marine Sciences, P.O. Box 315, Little River, CA 95456, California, United States;1. Department of Chemistry, University of Virginia, Charlottesville, VA 22904, United States;2. Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, United States;3. Nanoscale Materials Characterization Facility, Materials Science and Engineering Department, University of Virginia, Charlottesville, VA 22904, United States;1. College of Engineering and NanoSEC, University of Georgia, Athens, GA 30620, United States;2. Department of Mechanical Engineering, University of Texas at San Antonio, San Antonio, TX 78249, United States;1. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, 91109, USA;2. ATA Engineering, Inc., San Diego, CA, 92128, USA;1. Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC 29036, USA;2. Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA;3. Department of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA;1. Saratov State University, 83, Astrakhanskaya str., Saratov, Russia;2. Saratov Branch of Institute of Radioengineering and Electronics of RAS, 38, Zelenaya str., Saratov, Russia;3. Yuri Gagarin State Technical University of Saratov, 77 Politechnicheskaya street, Saratov, 410054, Russia;1. Department of Biological Sciences, Environmental Toxicology Graduate Program, Clemson University, Clemson, SC 29634, USA;2. The College of William & Mary, Gloucester Point, VA 23062, USA |
| |
| Abstract: | Glycine N-methyltransferase (GNMT) is a mediator in the methionine and folate cycles, and is responsible for the transfer of a methyl group from S-adenosylmethionine (SAM) to glycine forming S-adenosylhomocysteine (SAH) and sarcosine. All the known DNA methyltransferases use SAM as a methyl donor thus, GNMT is critically involved in regulation of DNA methylation. Altered GNMT activities have been associated with liver pathologies including hepatocellular carcinoma. The homotetramer form of GNMT is enzymatically active, but the homodimeric form has been suggested as the 4S PAH-binding protein which may mediate CYP1A expression. To further understand the role of GNMT in benzo(a)pyrene (BaP)-related toxicity, full length Fundulus heteroclitus GNMT cDNA was cloned from adult liver. The open reading frame (ORF) of GNMT is 888 base pairs long and encodes a deduced protein of 295 amino acids which has 74% identity with human GNMT. Expression of GNMT mRNA was determined by quantitative RT-PCR. In unfertilized, 2 days postfertilization (dpf), and 3 dpf embryos GNMT was constitutively higher than in 4, 7, 10 or 14 dpf embryos. Embryos were also exposed to waterborne BaP at 10 and 100 μg L?1, and by 10 dpf the higher BaP dose caused increased expression of GNMT mRNA. These results suggest that PAH exposure may alter expression of an important physiological methylation mediator. Future work will be necessary to determine enzyme level effects of BaP exposure as well. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
