Vaucheria Genome Project

Samsung Science and Technology Foundation (link)

Figure. Four species from the Vaucheria-lineage showing distinct sexual types and their phylogenetic trend from asexual to the dioecious sexual type

Project Summary

Sexual reproduction is a fundamental and inextricable part of the eukaryotic life forms. Sex gives the advantage of creating tremendously diverse progenies, although it is more expensive than its asexual counterpart. Within the eukaryotic tree of life, there is a general evolutionary trend from asexuality to early hermaphroditic sex and then to obligate dioecious sex. How sex has emerged and diversified in eukaryotic lineages, however, remains elusive, despite ceaseless quests for proper explanations. One of the reasons for the difficulty is that the existing animal and plant model organisms are complex and they have limited sexual types.

From my previous research in the field of photosynthetic marine organisms, I found that Vaucheria, a yellow-green alga, could be a novel model system for evolutionary studies of sexual reproduction because, within this single genus, there are species with hermaphroditic, monoecious and dioecious reproductive types as well as three species that have reverted to their earlier types. Vaucheria, moreover, has a small genome size, is readily available from the field, and easily cultured in the lab. Here I propose to decipher the principles of evolution of sexual reproduction using Vaucheria as a model organism. More specifically, this research consists of an investigation focused on three critical questions.

  • First, what genes induce changes in sexual characters and types?
  • The second specific question will address the question of how sex-related genes interact with each other.
  • My third question asks how the sex-related genes influence phenotypic changes.

By combining genomic, developmental, and evolutionary analyses of sexual development in Vaucheria, we will be able to study the basic principles of sexual evolution that have resulted in the dazzling array of sexual strategies in eukaryotes. Furthermore, we will be able to answer to the question whether or not the independent events in eukaryotic sexual evolution share common features and principles. This work will establish Vaucheria as a model system that can be widely used in the academic field of the evolution to reveal the secrets of sexual reproduction.