ATBF1-A protein, but not ATBF1-B, is preferentially expressed in developing rat brain.
The ATBF1 gene encodes transcription factors containing four homeodomains and multiple zinc finger motifs. However, the gene products have yet to be identified and the role remains unknown in vivo. In this study, we raised an antiserum for ATBF1 and found high levels of expression of ATBF1 in developing rat brain. Western and Northern blot analyses detected a 400 kDa protein and 12.5 kb mRNA in developing rat brain, respectively; both corresponding to ATBF1-A but not the B isoform. The protein was highly expressed in the midbrain and diencephalon and mRNA was highly expressed in the brainstem, mostly in embryo and neonatal brain. Immunohistochemistry identified postmitotic neurons in the brainstem as the major site of ATBF1 expression, and the expression levels varied depending on age of and location in the brain. Expression was transient and weak in the precursor cells at early neurogenesis. ATBF1 decreased postnatally, but remained in mature neurons, including those expressing DOPA decarboxylase (DDC). High levels of ATBF1 were expressed in precursor cells in accordance with neurogenesis and were continued to the mature neurons in specific areas such as the inferior colliculus. Expression was not significant from precursor cells to mature neurons in the cerebral cortex and hippocampus. ATBF1 and its Drosophila homolog, Zfh-2, are known to regulate cell differentiation and proliferation via the interaction with either of the basic helix-loop-helix transcription factors, c-myb, or the DDC gene. Together with these reported functions the expression features detected here suggest that ATBF1 may participate in the regulation of neuronal cell maturation or region-specific central nervous system differentiation.
Ishii
Yoko
Y
Faculty of Medicine, Toyama Medical and Pharmaceutical University, Toyama 930-0194, Japan.
Kawaguchi
Makoto
M
Takagawa
Kiyoshi
K
Oya
Takeshi
T
Nogami
Shigeharu
S
Tamura
Amane
A
Miura
Yutaka
Y
Ido
Akio
A
Sakata
Nobuo
N
Hashimoto-Tamaoki
Tomoko
T
Kimura
Tomoatsu
T
Saito
Takayoshi
T
Tamaoki
Taiki
T
Sasahara
Masakiyo
M
D000375:Aging / Q000235:genetics / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D001921:Brain / Q000196:embryology* / Q000254:growth & development* / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics*; D002455:Cell Division / Q000235:genetics; D004296:Dopa Decarboxylase / Q000378:metabolism; D005333:Fetus; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D018257:Helix-Loop-Helix Motifs / Q000235:genetics; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D007150:Immunohistochemistry; D009474:Neurons / Q000378:metabolism*; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*
D018398:Homeodomain Proteins; D020033:Protein Isoforms; D012333:RNA, Messenger; C489512:Zfhx3 protein, rat; D004296:Dopa Decarboxylase