Nuclear localization, DNA binding and restricted expression in neural and germ cells of zebrafish Dmrt3.
BACKGROUND
The DM (doublesex and male aberrant-3) genes implicated in sexual development in diverse metazoan organisms have been proved to be involved in development of non-gonadal tissues. The aim of the present study was to identify and characterize Dmrt3 (DM-related transcription factor 3) of zebrafish.


RESULTS
Zebrafish Dmrt3 has a conserved DMA domain, besides a common DM domain, which clustered it into the DMRTA subfamily. During embryogenesis, Dmrt3 expression increases gradually to a high level at pharyngula stage, which is restricted to the olfactory placode and the neural tube. In the juvenile zebrafish, the gene expression is first detected in undifferentiated gonad on 17 dpf (day post-fertilization). In adult, Dmrt3 is expressed only in the developing germ cells of both gonads, mainly in spermatogonia, spermatocytes and developing oocytes. The Dmrt3 has a functional NLS (nuclear localization signal) K(41)GHKR(45) within the DM domain, which ensures that Dmrt3 exerts its role in the nucleus. Moreover, EMSA (electrophoretic mobility-shift assay) indicates that the Dmrt3-derived DM polypeptide binds to similar sites of both targets of DSX (doublesex) and MAB-3 (male aberrant-3).


CONCLUSIONS
These results suggest that as a DNA-binding protein, zebrafish Dmrt3 may function in the nucleus as a potential transcription factor to exert potential roles in the development of the olfactory placode, the neural tube and germ cells.
Li
Qin
Q
Department of Genetics and Center for Developmental Biology, College of Life Sciences, Wuhan University, Wuhan 430072, People's Republic of China.
Zhou
Xiang
X
Guo
Yiqing
Y
Shang
Xuan
X
Chen
Hao
H
Lu
Heng
H
Cheng
Hanhua
H
Zhou
Rongjia
R
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002467:Cell Nucleus / Q000378:metabolism*; D017931:DNA Primers / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000378:metabolism; D004625:Embryo, Nonmammalian; D005260:Female; D017403:In Situ Hybridization; D008297:Male; D008969:Molecular Sequence Data; D009474:Neurons / Q000378:metabolism; D019913:Nuclear Localization Signals; D010053:Ovary / Q000378:metabolism; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D013737:Testis / Q000378:metabolism; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D015027:Zebrafish / Q000196:embryology; D029961:Zebrafish Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*
D017931:DNA Primers; D004268:DNA-Binding Proteins; D019913:Nuclear Localization Signals; D014157:Transcription Factors; D029961:Zebrafish Proteins; C530835:dmrt3a protein, zebrafish