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Electroporation of the Hindbrain to Trace Axonal Trajectories and Synaptic Targets in the Chick Embryo
Published on: May 29, 2013
Sexually dimorphic gene expression in the chick brain before gonadal differentiation.
1Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Korea.
Poultry Science
|April 11, 2009
Summary
Sexually dimorphic gene expression in chicken brains occurs before sexual development. This study identified specific genes potentially involved in neural sex differentiation in early embryos.
Area of Science:
- Neuroscience
- Developmental Biology
- Genetics
Background:
- Sexual differentiation of the brain is observed across vertebrate species, including chickens.
- The traditional view of hormonal dependence in brain sexual differentiation is being re-evaluated.
- Understanding the timing and genetic basis of neural sex differences is crucial.
Purpose of the Study:
- To investigate whether sexually dimorphic gene expression in the brain precedes gonadal differentiation in chickens.
- To identify specific genes that exhibit differential expression between male and female embryonic chicken brains.
- To explore the potential roles of these genes in neural development and sexual differentiation.
Main Methods:
- Utilized the Affymetrix GeneChip Chicken Genome Array to analyze gene expression in embryonic chicken brains.
- Identified differentially expressed genes between male and female brains at stage 29.
- Employed quantitative real-time PCR (qPCR) to validate microarray findings and examine stage-specific expression patterns.
Main Results:
- Identified 42 female-enhanced and 167 male-enhanced genes with sex-specific expression in stage 29 chicken embryos.
- Microarray results were confirmed by quantitative real-time PCR, demonstrating high efficacy.
- Expression patterns of identified genes were analyzed for stage-specific changes.
Conclusions:
- Sexually dimorphic gene expression in the chicken brain can occur prior to gonadal differentiation.
- A set of specific genes has been identified with potential roles in the sexual differentiation of neural function.
- These findings contribute to a revised understanding of brain sexual differentiation, highlighting early genetic influences.
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