Biologically meaningful expression profiling across species using heterologous hybridization to a cDNA microarray

Area of Science:

• Comparative genomics
• Functional genomics
• Evolutionary biology

Background:

• Understanding genotype-phenotype relationships is key in biology.
• Gene expression profiling via microarrays is crucial but limited to few model systems.
• Genomics enables expression profiling in non-traditional models for complex traits.

Purpose of the Study:

• To develop a microarray for the African cichlid fish, Astatotilapia burtoni.
• To assess the utility of heterologous hybridization for gene expression profiling across fish species.
• To establish a foundation for functional genomics in diverse, non-model organisms.

Main Methods:

• Construction of a microarray with ~4500 features from a brain-specific cDNA library.
• Utilization of heterologous hybridization for gene expression profiling in eight fish species.
• Quantification of gene expression profile concordance across species based on divergence times.

Main Results:

• A functional microarray for Astatotilapia burtoni was created.
• Consistent gene expression profiles were observed across species, even distantly related ones.
• The method's robustness decreased with increasing evolutionary distance between species.

Conclusions:

• Expression profiling is validated for functional genomics in a comparative context.
• This approach overcomes limitations of model systems for evolutionary and ecological studies.
• Provides a basis for analyzing complex traits in a wide array of organisms.