PUBLICATION

The Role of Fanconi Anemia/BRCA Genes in Zebrafish Sex Determination

Authors
Rodriguez-Mari, A., and Postlethwait, J.H.
ID
ZDB-PUB-111012-24
Date
2011
Source
Methods in cell biology   105: 461-490 (Chapter)
Registered Authors
Postlethwait, John H., Rodriguez-Mari, Adriana
Keywords
apoptosis, fanconi anemia, meiotic, ortholog, repair, sex determination
MeSH Terms
  • Animals
  • BRCA2 Protein/genetics*
  • BRCA2 Protein/metabolism
  • DNA Repair
  • Developmental Biology/methods*
  • Drug Discovery
  • Fanconi Anemia/drug therapy
  • Fanconi Anemia/genetics*
  • Fanconi Anemia/metabolism
  • Fanconi Anemia/pathology
  • Fanconi Anemia Complementation Group Proteins/genetics*
  • Fanconi Anemia Complementation Group Proteins/metabolism
  • Female
  • Genomic Instability
  • Germ Cells/cytology
  • Germ Cells/metabolism
  • Gonads/cytology
  • Gonads/metabolism
  • High-Throughput Screening Assays*
  • Homologous Recombination
  • Humans
  • Male
  • Meiosis
  • Mutation
  • Phenotype
  • Sex Determination Processes/genetics*
  • Small Molecule Libraries/therapeutic use
  • Zebrafish/genetics*
  • Zebrafish/metabolism
PubMed
21951543 Full text @ Meth. Cell. Biol.
Abstract
Fanconi anemia (FA) is a human disease of bone marrow failure, leukemia, squamous cell carcinoma, and developmental anomalies, including hypogonadism and infertility. Bone marrow transplants improve hematopoietic phenotypes but do not prevent other cancers. FA arises from mutation in any of the 15 FANC genes that cooperate to repair double stranded DNA breaks by homologous recombination. Zebrafish has a single ortholog of each human FANC gene and unexpectedly, mutations in at least two of them (fancl and fancd1(brca2)) lead to female-to-male sex reversal. Investigations show that, as in human, zebrafish fanc genes are required for genome stability and for suppressing apoptosis in tissue culture cells, in embryos treated with DNA damaging agents, and in meiotic germ cells. The sex reversal phenotype requires the action of Tp53 (p53), an activator of apoptosis. These results suggest that in normal sex determination, zebrafish oocytes passing through meiosis signal the gonadal soma to maintain expression of aromatase, an enzyme that converts androgen to estrogen, thereby feminizing the gonad and the individual. According to this model, normal male and female zebrafish differ in genetic factors that control the strength of the late meiotic oocyte-derived signal, probably by regulating the number of meiotic oocytes, which environmental factors can also alter. Transcripts from fancd1(brca2) localize at the animal pole of the zebrafish oocyte cytoplasm and are required for normal oocyte nuclear architecture, for normal embryonic development, and for preventing ovarian tumors. Embryonic DNA repair and sex reversal phenotypes provide assays for the screening of small molecule libraries for therapeutic substances for FA.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping