Distribution of AP-2 subtypes in the adult mouse brain.
In the mammalian central nervous system (CNS), transcription factor activator protein 2 (AP-2) is one of the critical regulatory factors for neural gene expression and neural development. As AP-2 has diverged into several subtypes, i.e. AP-2alpha, -2beta, and 2.2, we investigated the distribution of the AP-2 subtypes in the adult mouse brain by in situ hybridization using subtype-specific probes. Though AP-2 was essentially expressed in most regions of the brain, the hippocampus and cerebellum Purkinje cells exhibited a relatively high concentration of transcripts of any of the AP-2 subtypes. Among AP-2alpha variants, the expression of variant 1 was considerably lower than that of variant 3. Hence, the expression pattern of AP-2alpha variant 3 is suggested to represent the major gene expression of AP-2alpha. On the other hand, the expression of AP-2beta messenger RNA (mRNA) was higher than that of AP-2alpha in many regions. Especially, the olfactory bulb, hippocampus, cerebellum, and cerebral cortex contained an abundance of these mRNAs. Different from those of AP-2alpha, AP-2beta mRNAs were detected in considerable amounts in the glanular cells as well as in Purkinje cells. AP-2.2 gene expression was weak throughout the brain. Consequently, we found that various AP-2 subtypes and variants were expressed in a similar distribution pattern with each having its own specific intensity but that their precise distribution profiles were not exactly the same. In the mature brain, AP-2 is thought to regulate neural gene expression through specific and redundant association with a target gene.
Shimada
M
M
Department of Biology, Faculty of Science, Chiba University, Japan.
Konishi
Y
Y
Ohkawa
N
N
Ohtaka-Maruyama
C
C
Hanaoka
F
F
Makino
Y
Y
Tamura
T
T
D000818:Animals; D002531:Cerebellum / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D006624:Hippocampus / Q000378:metabolism*; D017403:In Situ Hybridization; D051379:Mice; D008813:Mice, Inbred ICR; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D050656:Transcription Factor AP-2; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
D004268:DNA-Binding Proteins; D012333:RNA, Messenger; C493668:Tfap2a protein, mouse; C493669:Tfap2b protein, mouse; D050656:Transcription Factor AP-2; D014157:Transcription Factors