PUBLICATION
Differential tissue distribution, developmental programming, estrogen regulation and promoter characteristics of cyp19 genes in teleost fish
- Authors
- Callard, G.V., Tchoudakova, A.V., Kishida, M., and Wood, E.
- ID
- ZDB-PUB-020220-2
- Date
- 2001
- Source
- The Journal of steroid biochemistry and molecular biology 79(1-5): 305-314 (Journal)
- Registered Authors
- Callard, Gloria V., Kishida, Mitsuyo, Wood, Elizabeth
- Keywords
- Cytochrome P450 aromatase, Brain, Ovary, Fish
- MeSH Terms
-
- Tissue Distribution
- Transcription Factors
- Isoenzymes/genetics
- Isoenzymes/metabolism
- Receptors, Cytoplasmic and Nuclear
- Gene Expression Regulation, Developmental
- Cell Line
- Goldfish/genetics*
- Goldfish/growth & development
- Goldfish/metabolism*
- Models, Biological
- Zebrafish/genetics*
- Zebrafish/growth & development
- Zebrafish/metabolism*
- Receptors, Estrogen/metabolism
- Zebrafish Proteins
- Gene Expression Regulation, Enzymologic
- Aromatase/genetics*
- Brain/enzymology
- Brain/growth & development
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Animals
- Female
- Ovary/enzymology
- DNA-Binding Proteins
- Transfection
- Estrogens/metabolism*
- Promoter Regions, Genetic
- PubMed
- 11850237 Full text @ Steroid Biochem. Mol. Biol.
Citation
Callard, G.V., Tchoudakova, A.V., Kishida, M., and Wood, E. (2001) Differential tissue distribution, developmental programming, estrogen regulation and promoter characteristics of cyp19 genes in teleost fish. The Journal of steroid biochemistry and molecular biology. 79(1-5):305-314.
Abstract
Teleost fish are characterized by exceptionally high levels of brain estrogen biosynthesis when compared to the brains of other vertebrates or to the ovaries of the same fish. Goldfish (Carassius auratus) and zebrafish (Danio rerio) have utility as complementary models for understanding the molecular basis and functional significance of exaggerated neural estrogen biosynthesis. Multiple cytochrome P450 aromatase (P450arom) cDNAs that derive from separate gene loci (cyp19a and cyp19b) are differentially expressed in brain (P450aromB[dbl greater-than sign]A) and ovary (P450aromA[dbl greater-than sign]B) and have a different developmental program (B[dbl greater-than sign]A) and response to estrogen upregulation (B only). As measured by increased P450aromB mRNA, a functional estrogen response system is first detected 24--48h post-fertilization (hpf), consistent with the onset of estrogen receptor (ER) expression ([alpha], [beta], and [gamma]). The 5[prime prime or minute]-flanking region of the cyp19b gene has a TATA box, two estrogen response elements (EREs), an ERE half-site (ERE1/2), a nerve growth factor inducible-B protein (NGFI-B)/Nur77 responsive element (NBRE) binding site, and a sequence identical to the zebrafish GATA-2 gene neural specific enhancer. The cyp19a promoter region has TATA and CAAT boxes, a steroidogenic factor-1 (SF-1) binding site, and two aryl hydrocarbon receptor (AhR)/AhR nuclear translocator factor (ARNT) binding motifs. Both genes have multiple potential SRY/SOX binding sites (16 and 8 in cyp19b and cyp19a, respectively). Luciferase reporters have basal promoter activity in GH3 cells, but differences (a[dbl greater-than sign]b) are opposite to fish pituitary (b[dbl greater-than sign]a). When microinjected into fertilized zebrafish eggs, a cyp19b promoter-driven green fluorescent protein (GFP) reporter (but not cyp19a) is expressed in neurons of 30--48hpf embryos, most prominently in retinal ganglion cells (RGCs) and their projections to optic tectum. Further studies are required to identify functionally relevant cis-elements and cellular factors, and to determine the regulatory role of estrogen in neurodevelopment.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping