Experiment

The Second Session of CsPINs Experiment Completed

All times are Japan Standard Time (JST)

The second session of Dynamism of Auxin Efflux Facilitators, CsPINs, Responsible for Gravity-regulated Growth and Development in Cucumber (CsPINs)*, which has been performed using the Cell Biology Experiment Facility (CBEF) on board Kibo, was completed.

*Principal Investigator (PI): Hideyuki Takahashi, Professor, Tohoku University

Three experiments were planned during the second session of CsPINs, of which the first experiment was conducted on June 26, and the second one from July 5 to 6, and the third one from July 7 to 8, respectively. As the storage of obtained sample was found unsuccessful for the second experiment(*1), its retry was conducted from July 14 to 15 and completed at 0:40 a.m. on July 16. Obtained samples are to be delivered to the ground on board the space shuttle Atlantis (STS-135 mission).

*1 Some function of the automated storage equipment didn't work. Parts replacement was made for the retry.

CsPINs consists of a total of eight experiments of three sessions. Two experiments of the first session were held for four days, between April 26 and April 29, and the obtained samples were delivered to the ground by the space shuttle Endeavour (STS-134 mission) and are now being analyzed. Experiment date for the third session is being arranged.

"CsPINs" is a protein group that controls activity and distribution of Auxin, a plant hormone, which has an essential role in coordination of a plant growth. This experiment focuses on "CsPIN1", which is assumed to be involved in gravimorphogenesis(*2) in plant, and "CsPIN5", which is assumed to be involved in hydrotropism, and aims at understanding their activities. To be more precise, set cucumber seeds in CBEF on board Kibo and germinate them in various conditions, with gravity or microgravity, or with different water contents. Then analyze the status of CsPIN1 and CsPIN5 that exist in cucumber roots at each developmental stage.

*2 Morphogenesis is the biological process that causes a new tissue or organ to form into an organism by heterogenesis or celluar differentiation whereas gravimorphogenesis is the formation by the gravitational effect as a plant root grows downward.

If these protein activities are understood, the findings will be applied to the root growth orientation control or plant organ formation control. It is hoped that the control techniques will eventually be contributed to the plant cultivation technology, and in the future, space plant factories.

Special message from the Principal Investigator (PI)

We very much appreciate Astronaut Furukawa aboard the ISS for conducting all the second session very accurately. Thanks to his contribution, cucumber root grew smoothly, and the second session has successfully completed. I look forward to receiving them after a return of the space shuttle Atlantis (STS-135 mission).

*All times are Japan Standard Time (JST)