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A parasitic selfish gene that affects host promiscuity.
Paulina Giraldo-Perez1, Matthew R Goddard
1The School of Biological Sciences, The University of Auckland, , Private Bag 92109, Auckland Mail Centre, Auckland, New Zealand.
Proceedings. Biological Sciences
|September 20, 2013
Summary
Selfish genes, like homing endonuclease genes (HEGs), can be parasitic, imposing a selective load on yeast hosts. These selfish genetic elements may also increase host sexual behavior, aiding their own spread.
Area of Science:
- Evolutionary genetics
- Molecular biology
- Yeast genetics
Background:
- Selfish genes are genetic elements that replicate preferentially, often without benefiting their host.
- Homing endonuclease genes (HEGs) are a type of selfish gene typically considered benign.
- The impact of selfish genes on host fitness and behavior is not fully understood.
Purpose of the Study:
- To investigate the fitness costs associated with carrying HEGs in Saccharomyces cerevisiae.
- To determine if HEGs can influence host sexual behavior and mating propensity.
- To evaluate the potential role of HEGs in the evolution of sex.
Main Methods:
- Quantifying the selective load imposed by HEGs in yeast populations.
- Assessing changes in host sexual behavior in the presence of HEGs.
- Analyzing the transmission dynamics of HEGs in relation to host reproduction.
Main Results:
- Carrying HEGs imposes a significant selective load (approx. 1-2%) on Saccharomyces cerevisiae.
- HEGs can increase the propensity of yeast hosts to engage in sexual reproduction.
- Increased sexual behavior, coupled with non-Mendelian inheritance, may promote HEG spread.
Conclusions:
- HEGs are not benign but can be parasitic, impacting host fitness.
- Selfish genes can manipulate host behavior, specifically increasing sexual activity.
- The ability of selfish genes to influence host promiscuity may have played a role in the evolution of sexual reproduction.
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