Preservation of duplicate genes by originalization
- 89 Downloads
Neofunctionalization, subfunctionalization and increasing gene dosage were proposed to be the possible ways to explain duplicate-gene preservation in previous studies. However, in some natural populations, such as yeast Saccharomyces cerevisiae, a considerable proportion of the duplicate genes originated from ancient whole genomic duplication (WGD) is preserved till now, which cannot be sufficiently explained by these mechanisms. In this article, we present another possible way to explain this conundrum—originalization, by which duplicate genes are both preserved intact at a high frequency in the population under only purifying selection. With approximate equal rates of mutation at the two duplicated loci, analytical, numerical and simulation results consistently show that the mean time to nonfunctionalization for unlinked haploinsufficient gene duplication might become markedly prolonged, which results from originalization. These theoretical results imply that originalization might be an alternative effective and temporary way of preserving duplicate genes.
KeywordsGene duplication Originalization Recombination Selection Preservation
This work is partly supported by funds from Yunan University and we acknowledge assistance from the Center for High Performance Computation of Yunnan University. We thank anonymous reviewers for many valuable comments and also thank Drs. Huatao Deng, Tianhong Xu, Shuqun Liu, Yang Shen, Xianda Lu, Ren Huang, Suhua Shi, Lianghu Qu, Yupeng Cun and Michael Lynch for their assistance and Sara Barton for editorial review. The junior author also graciously acknowledges his fellowships from GuangDong Institute for Monitoring Laboratory Animals and Tarim Agricultural University.
- Kincaid D, Cheney W (2002) Numerical analysis: mathematics of scientific computing, 3rd edn. Brooks/Cole Publication Co, Pacific GroveGoogle Scholar
- Ohno S (1970) Evolution by gene duplication. Springer-Verlag, New YorkGoogle Scholar
- Rice SH (2004) Evolutionary theory: mathematical and conceptual foundations. Sinauer Associates Inc, SunderlandGoogle Scholar