The NR1 subunit, a product of a single gene, is the key subunit as functional NMDA receptors are not formed without it. NMDA receptors are an important site of action of ethanol. Chronic ethanol exposure up regulates NMDA receptor number/function in vivo and in vitro with a concomitant increase in NR1 and NR2B protein levels. Out of four NR1 splice variants, chronic ethanol favors the expression of only one NR1splice variant (NR1-4a) at the mRNA &polypeptide levels in cultured fetal cortical neurons (FCN) (Kumari, 2001) uggesting an altered physiology and pharmacology of NMDA receptors in ethanol treated neurons. Furthermore, chronic ethanol-mediated increase in NR1 mRNA half-life in vitro requires de novo protein synthesis. A closer molecular examination identified two cis-acting regions in the NR1 3'UTR. One cis- acting region interacts with three trans-acting proteins and chronic ethanol up regulates one trans-acting protein in FCN (Anji et al., 2004). Long term plan of this project is to elucidate molecular mechanism(s) involved in ethanol-mediated regulation of NR1 subunit in FCN. In this grant, the following are proposed: (1) delineate mechanism(s) including splicing in the nucleus that alter mRNA levels of NR1 splice variants in ethanol treated FCN;determine the importance of RNA-protein interactions on NR1 mRNA (2) stability;(3) transport and localization;and (4) translation. These goals will be achieved by (a) determining half-lives of NR1 splice variants and splicing of exon 5 in FCN;(b) generating &testing chimeric plasmids, by RNAi, transient transfection or stable transfection to determine role of cis and trans factors on NR1 mRNA stability, NR1 mRNA transport (half-life study using actinomycin-D);transport and localization (by in situ hybridiztion & immunocytochemistry);and translation (using an in vitro translation system). A more thorough understanding of the pertinent molecular mechanisms through which ethanol modulates R1 mRNA stability/translation may permit the design of novel therapeutic approaches to alcohol-related diseases. NMDA receptors mediate neurotransmission and play important roles in memory formation. These receptors are also effected by a chronic alcohol consumption and play a role in development alcohol dependence. A better understanding of the effects of alcohol on NMDA receptors regulation in the brain will lead to better treatment for alcoholism. -

Agency
National Institute of Health (NIH)
Institute
National Institute on Alcohol Abuse and Alcoholism (NIAAA)
Type
Research Project (R01)
Project #
3R01AA012070-10S1
Application #
8690257
Study Section
Neurotoxicology and Alcohol Study Section (NAL)
Program Officer
Reilly, Matthew
Project Start
1999-02-01
Project End
2014-07-31
Budget Start
2013-07-01
Budget End
2014-07-31
Support Year
10
Fiscal Year
2013
Total Cost
$33,600
Indirect Cost
$11,200
Name
Kansas State University
Department
Anatomy/Cell Biology
Type
Schools of Veterinary Medicine
DUNS #
929773554
City
Manhattan
State
KS
Country
United States
Zip Code
66506
Anji, Antje; Kumari, Meena (2016) Guardian of Genetic Messenger-RNA-Binding Proteins. Biomolecules 6:4
Anji, Antje; Miller, Hayley; Raman, Chandrasekar et al. (2015) Expression of α-subunit of α-glucosidase II in adult mouse brain regions and selected organs. J Neurosci Res 93:82-93
Velders, Fleur P; Kuningas, Maris; Kumari, Meena et al. (2011) Genetics of cortisol secretion and depressive symptoms: a candidate gene and genome wide association approach. Psychoneuroendocrinology 36:1053-61
Zabaneh, Delilah; Kumari, Meena; Sandhu, Manj et al. (2011) Meta analysis of candidate gene variants outside the LPA locus with Lp(a) plasma levels in 14,500 participants of six White European cohorts. Atherosclerosis 217:447-51
Anji, Antje; Kumari, Meena (2011) A cis-acting region in the N-methyl-d-aspartate R1 3'-untranslated region interacts with the novel RNA-binding proteins beta subunit of alpha glucosidase II and annexin A2--effect of chronic ethanol exposure in vivo. Eur J Neurosci 34:1200-11
Anji, Antje; Kumari, Meena (2009) Differentiated P19 cells express N-methyl-D-aspartate receptor 1 mRNA binding trans-acting proteins and four N-methyl-D-aspartate receptor 1 splice variants comparable to those in cultured fetal cortical neurons. J Neurosci Res 87:1591-601
Kumari, Meena; Anji, Antje; Woods Jr, Henri et al. (2003) The molecular effects of alcohol: clues to the enigmatic action of alcohol. Ann N Y Acad Sci 993:82-94; discussion 123-4
Anji, Antje; Shaik, Kamran A; Kumari, Meena (2003) Effect of ethanol on lipid-mediated transfection of primary cortical neurons. Ann N Y Acad Sci 993:95-102; discussion 123-4
Kumari, M (2001) Differential effects of chronic ethanol treatment on N-methyl-D-aspartate R1 splice variants in fetal cortical neurons. J Biol Chem 276:29764-71