Overexpression of dopamine receptor genes and their products in the postnatal rat brain following maternal n-3 fatty acid dietary deficiency.
A combination of PCR-Select cDNA subtraction and gene array hybridization was used to identify differentially expressed genomic markers in brains of rats fed for 3 weeks in utero and 2 weeks after birth on an n-3 polyunsaturated fatty acid (PUFA)-deficient diet supplied to dams. Total RNA was isolated, switch mechanism at 5'-end of the RNA transcripts (SMART) applied and used for PCR-Select subtraction of PUFA-deficient and adequately-fed control preparations. Subtracted and amplified ds-cDNA end-products were fragmented, terminally labeled with biotin-ddUTP and hybridized with a RN-U34A gene array. A 10-fold increase in potential genes with log2(Tester/Driver) = 1.4 was found compared with traditional gene array technology when the same chip was tested using non-subtracted targets. Reverse transcription-real-time relative PCR confirmed 30% of the transcripts. Among the validated transcripts, D1 and D2 receptors for dopamine (DA), were most prominent among a number of over-expressed neurotransmitter receptors and retinoic acid receptor (RXR alpha-2 and alpha-1). Immunohistochemical staining of brain sections from 2-week-old pups revealed a substantial enrichment of the D2 receptor in discrete regions of the mesolimbic and mesocortical pathways as well as in a large number of brain areas from the n-3 PUFA-deficient pups. Punches of the same areas run on western blots showed similar results. The overwhelming expression of D1 and D2 receptors may be attributed to a behavioral hypersensitivity caused by the possible impairment of DA production during brain development, which may have implications in certain disorders of the nervous system.
Kuperstein
F
F
Department of Neurobiology, Weizmann Institute of Science Rehovot, Israel.
Yakubov
E
E
Dinerman
P
P
Gil
S
S
Eylam
R
R
Salem
N
N
Yavin
E
E
D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D015153:Blotting, Western; D001923:Brain Chemistry / Q000235:genetics*; D002540:Cerebral Cortex / Q000378:metabolism / Q000502:physiology; D018076:DNA, Complementary / Q000096:biosynthesis; D004032:Diet; D005227:Fatty Acids / Q000008:administration & dosage; D015525:Fatty Acids, Omega-3 / Q000502:physiology*; D005260:Female; D015870:Gene Expression / Q000502:physiology; D005786:Gene Expression Regulation; D015723:Gene Library; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008032:Limbic System / Q000378:metabolism / Q000502:physiology; D009419:Nerve Tissue Proteins / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D012313:RNA / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D011954:Receptors, Dopamine / Q000096:biosynthesis* / Q000235:genetics*; D017447:Receptors, Dopamine D1 / Q000502:physiology; D017448:Receptors, Dopamine D2 / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction
D018076:DNA, Complementary; D005227:Fatty Acids; D015525:Fatty Acids, Omega-3; D009419:Nerve Tissue Proteins; D011954:Receptors, Dopamine; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D012313:RNA