A promoter-associated polymorphic repeat modulates PAX-6 expression in human brain.
The PAX-6 gene plays a critical role in neurodevelopment and brain plasticity. While transcription of human PAX-6 is regulated by alternate usage of two distinct promoters termed A and B, expression in adult human brain is primarily controlled by promoter B. We now report that a novel polymorphic dinucleotide repeat sequence with the structure (AC)m(AG)n is located approximately 1 kb upstream of the transcription initiation site associated with promoter B. PCR-based systematic screening for length variations in a caucasian population showed a skewed distribution of multiple alleles containing between 24 and 36 repeat units. In 217 unrelated individuals, the frequency of alleles in the range between 25 and 29 repeats was 90%, with the 26 repeat allele alone accounting for 50%; the heterozygosity rate was 65%. Variants of this PAX-6 gene-linked polymorphic region (PAX-6LPR) had different transcriptional efficiencies when fused to a luciferase reporter gene and transfected into Cos-7 cells. Promoter activity of variants with >/=29 repeats was 4- to 9-fold higher than that of the 26 repeat allele. The influence of the PAX-6LPR on PAX-6 expression was confirmed in postmortem cerebellum from individuals with different genotypes. mRNA levels were 2-fold higher in genotypes with long alleles compared to those with short alleles. Allelic variation in PAX-6 expression may be a determinant of interindividual differences in brain plasticity and function.
Okladnova
O
O
Department of Psychiatry, University of Würzburg, Füchsleinstrasse 15, Würzburg, 97080, Germany.
Syagailo
Y V
YV
Tranitz
M
M
Stöber
G
G
Riederer
P
P
Mössner
R
R
Lesch
K P
KP
D000483:Alleles; D001921:Brain / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000235:genetics*; D018900:Dinucleotide Repeats / Q000235:genetics*; D005136:Eye Proteins; D005786:Gene Expression Regulation / Q000235:genetics*; D017930:Genes, Reporter / Q000235:genetics; D018398:Homeodomain Proteins; D006801:Humans; D009419:Nerve Tissue Proteins / Q000235:genetics; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics; D012097:Repressor Proteins; D044465:White People
D004268:DNA-Binding Proteins; D005136:Eye Proteins; D018398:Homeodomain Proteins; D009419:Nerve Tissue Proteins; D000071841:PAX6 Transcription Factor; C000605730:PAX6 protein, human; D051761:Paired Box Transcription Factors; D012333:RNA, Messenger; D012097:Repressor Proteins