Heterosis as a consequence of regulatory incompatibility

BMC Biology

Research Article

Eyal Shimoni¹  Ghil Jona²  Naama Barkai³  Sharon Reikhav³  Michal Breker³  Maya Schuldiner³  Dana Bar-Zvi³  Rebecca H. Herbst⁴  Ilya Soifer⁵  Avraham A. Levy⁶ 

[1] Department of Chemical Research Support, Weizmann Institute of Science, 7610001, Rehovot, Israel;Department of Life Sciences Core Facilities, Weizmann Institute of Science, 7610001, Rehovot, Israel;Department of Molecular Genetics, Weizmann Institute of Science, 7610001, Rehovot, Israel;Department of Molecular Genetics, Weizmann Institute of Science, 7610001, Rehovot, Israel;Broad Institute of MIT and Harvard, 02142, Cambridge, MA, USA;Department of Systems Biology, Harvard Medical School, 02114, Boston, MA, USA;Department of Molecular Genetics, Weizmann Institute of Science, 7610001, Rehovot, Israel;Current affiliation: Calico Labs, 94080, South San Francisco, CA, USA;Plant and Environmental Sciences Department, Weizmann Institute of Science, 7610001, Rehovot, Israel;

关键词: Hybrid vigor;    Heterosis;    Incompatibility;    Budding yeast;   

DOI  :  10.1186/s12915-017-0373-7

 received in 2017-02-03, accepted in 2017-04-11,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundThe merging of genomes in inter-specific hybrids can result in novel phenotypes, including increased growth rate and biomass yield, a phenomenon known as heterosis. Heterosis is typically viewed as the opposite of hybrid incompatibility. In this view, the superior performance of the hybrid is attributed to heterozygote combinations that compensate for deleterious mutations accumulating in each individual genome, or lead to new, over-dominating interactions with improved performance. Still, only fragmented knowledge is available on genes and processes contributing to heterosis.ResultsWe describe a budding yeast hybrid that grows faster than both its parents under different environments. Phenotypically, the hybrid progresses more rapidly through cell cycle checkpoints, relieves the repression of respiration in fast growing conditions, does not slow down its growth when presented with ethanol stress, and shows increased signs of DNA damage. A systematic genetic screen identified hundreds of S. cerevisiae alleles whose deletion reduced growth of the hybrid. These growth-affecting alleles were condition-dependent, and differed greatly from alleles that reduced the growth of the S. cerevisiae parent.ConclusionsOur results define a budding yeast hybrid that is perturbed in multiple regulatory processes but still shows a clear growth heterosis. We propose that heterosis results from incompatibilities that perturb regulatory mechanisms, which evolved to protect cells against damage or prepare them for future challenges by limiting cell growth.

【 授权许可】

CC BY   
© Barkai et al. 2017