A quantitative regional expression profile of EAAT2 known and novel splice variants reopens the question of aberrant EAAT2 splicing in disease.
The glutamate transporter 1 (GLT1) in rodents, or EAAT2 in humans, is alternatively spliced in a complex manner including the use of multiple 5' and 3' untranslated regions and several coding variants. We used quantitative RT-PCR to profile these splice variants in human and rat brain. We also used RT-PCR and Northern blotting to demonstrate that a novel isoform of GLT1b has an approximately 11kb 3' UTR extending through intron 9, exon 10 and approximately 5kb into the 3' untranslated region of GLT1. However, our most important finding concerns an aberrant transcript lacking exon 9, which contains a motif permitting translocation from the endoplasmic reticulum. This variant had previously been associated with amyotrophic lateral sclerosis until several groups reported high levels in normal brain tissue. In contrast, our data shows that this aberrant transcript is present at 0.1-0.2% of the major EAAT2 isoforms.
Lauriat
Tara L
TL
Department of Psychiatry, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1229, New York, NY 10029, United States.
Richler
Esther
E
McInnes
L Alison
LA
D020413:3' Untranslated Regions; D017398:Alternative Splicing; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D001921:Brain / Q000378:metabolism; D017931:DNA Primers; D027342:Excitatory Amino Acid Transporter 2 / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008297:Male; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction
D020413:3' Untranslated Regions; D017931:DNA Primers; D027342:Excitatory Amino Acid Transporter 2; D012333:RNA, Messenger