| Project/Area Number |
26281031
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Partial Multi-year Fund |
|---|
| Section | 一般 |
|---|
| Research Field |
Environmental impact assessment
|
|---|
| Research Institution | Kyoto University |
|---|
Principal Investigator |
Yoshida Takashi 京都大学, (連合)農学研究科(研究院), 准教授 (80305490)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
左子 芳彦 京都大学, (連合)農学研究科(研究院), 教授 (60153970)
金子 貴一 京都産業大学, 公私立大学の部局等, 教授 (80370922)
|
|---|
| Project Period (FY) |
2014-04-01 – 2017-03-31
|
| Project Status |
Completed (Fiscal Year 2016)
|
| Budget Amount *help |
¥16,120,000 (Direct Cost: ¥12,400,000、Indirect Cost: ¥3,720,000)
Fiscal Year 2016: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000)
Fiscal Year 2015: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000)
Fiscal Year 2014: ¥8,580,000 (Direct Cost: ¥6,600,000、Indirect Cost: ¥1,980,000)
|
|---|
| Keywords | バクテリオファージ / ラン藻 / ミクロキスティス / 共進化 |
|---|
| Outline of Final Research Achievements |
The cyanobacterium Microcystis frequently forms massive blooms in global freshwaters. Our previous genomic analyses on CRISPR arrays, which a marker for viral infection history, suggest that Microcystis and phage have co-evolved based on a frequency-dependent selection. The aim of this study is to understand co-evolutionary dynamics of Microcystis and phage in natural settings. In this field study, a CRISPR-related genotype (CT19) occupied in a Microcystis bloom and the CT19 consisted of the two major variants. These major CTs co-existed and oscillated throughout the sampling periods. Meanwhile few variations, which is derived from the acquisition of new spacers or the lack of spacers at the leader-end of the major variants, were observed. These indicate that Microcystis and phage co-evolution not only creates new genetic variations but also maintains their genetic diversity in a bloom. Further a growth experiment suggested that genetic change basically lessened host fitness.
|
