摘要
Documenting the sex and sexual reproduction of the microalgae is very difficult, as most of the results are based on the microscopic observation that can be heavily influenced by genetic, physiological and environmental conditions. Understanding the reproduction strategy of some microalgae is required to breed them in large scale culture industry. Instead of direct observation of sex and sexual reproduction under microscope, the whole set or the majority of core meiosis genes may evidence the sex and sexual reproduction in the unicellular algae, as the meiosis is necessary for maintaining the genomic stability and the advantages of genetic recombination. So far, the available genome sequences and bioinformatic tools （in this study, homolog searching and phylogenetic analysis） allow us to propose that at least 20 core meiosis genes （among them 〉6 must be meiosis specific） are enough for an alga to maintain its sexual reproduction. According to this assumption and the genome sequences, it is possible that sexual reproduction was carried out by Micromonas pusilla and Cyanidiosehyzon merolae, while asexual reproduction was adopted by Bigelowiella natans, Guillardia theta, Nannochloropsis gaditana, N. oeeanica, Chlorella variablis, Phaeodactylum tricornutum and Thalassiosira pseu- donana. This understanding will facilitate the breeding trials of some economic microalgae （e.g., N. gaditana, N. oceanica, C. vari- ablis and P. tricornutum）. However, the reproduction strategies of these microalgae need to be proved by further biological experiments.
Documenting the sex and sexual reproduction of the microalgae is very difficult, as most of the results are based on the microscopic observation that can be heavily influenced by genetic, physiological and environmental conditions. Understanding the reproduction strategy of some microalgae is required to breed them in large scale culture industry. Instead of direct observation of sex and sexual reproduction under microscope, the whole set or the majority of core meiosis genes may evidence the sex and sexual reproduction in the unicellular algae, as the meiosis is necessary for maintaining the genomic stability and the advantages of genetic recombination. So far, the available genome sequences and bioinformatic tools(in this study, homolog searching and phylogenetic analysis) allow us to propose that at least 20 core meiosis genes(among them ≥6 must be meiosis specific) are enough for an alga to maintain its sexual reproduction. According to this assumption and the genome sequences, it is possible that sexual reproduction was carried out by Micromonas pusilla and Cyanidioschyzon merolae, while asexual reproduction was adopted by Bigelowiella natans, Guillardia theta, Nannochloropsis gaditana, N. oceanica, Chlorella variablis, Phaeodactylum tricornutum and Thalassiosira pseudonana. This understanding will facilitate the breeding trials of some economic microalgae(e.g., N. gaditana, N. oceanica, C. variablis and P. tricornutum). However, the reproduction strategies of these microalgae need to be proved by further biological experiments.
基金
financially supported by National Science and Technology Supporting Program of China (2011BAD14B01)
National Natural Science Foundation of China (31270408)
Key Laborotary of Marine Bioactive Substance of State Oceanic Administration of China, The First Institute of Oceanography
