제 548회 생명과학연구소 정기세미나_공삼근 교수님(공주대)

일시: 2021년 11월 11일 (목) 오후5시

zoom link: https://kangwon-ac-kr.zoom.us/j/84628898516?pwd=aXNmblhVR1FKdi9zMmZNakdET3IwZz09

Molecular basis of chloroplast photorelocation movement in Arabidopsis 

공삼근 교수(공주대학교 생명과학과)

Plants have evolved unique responses to fluctuating light conditions in their environment. One such response, chloroplast photorelocation movement, optimizes photosynthesis under weak light by the accumulation of chloroplasts at the periclinal side of the cell (accumulation response) and prevents photodamage under strong light by the avoidance of chloroplasts to the anticlinal side of the cell (avoidance response). Phototropins (phot1 and phot2 in Arabidopsis) redundantly regulate the accumulation response under weak light conditions, while phot2 solely regulates the avoidance response under strong light conditions. The light-responsive chloroplast movements are driven by dynamic reorganizations of chloroplast actin (cp-actin) filaments. CHLOROPLAST UNUSUAL POSITIONING 1 (CHUP1) plays a pivotal role in chloroplast photorelocation movement as a key player in the regulation of cp-actin filaments. Functional fluorescently tagged CHUP1 colocalized with and was coordinately reorganized with cp-actin filaments on the chloroplast outer envelope during chloroplast movement. The distribution of CHUP1 was reversibly regulated in a blue light- and phototropin-dependent manner. X-ray crystallography indicated that the CHUP1 C-terminal domain shares structural similarity with the formin homology 2 (FH2) domain, although there is no sequence similarity between the two domains. The CHUP1 C-terminal domain stimulated actin polymerization in the presence of profilin by promoting nucleation in vitro. Taken together, our results suggest that CHUP1 is a novel, plant-specific actin nucleator that has evolved for cp-actin-based chloroplast photorelocation movement.

학력 및 약력

1990-1997   경북대학교 유전공학과, 이학사

1997-1999   경북대학교 유전공학과, 이학석사

2002-2006   교토대학 식물학과, 이학박사

2006-2008   일본 기초생물학연구소(NIBB) 광생물학부문, JSPS 외국인 특별연구원

2008-2015   큐슈대학 생물학과, 학술연구원, 연구조교수

2015-2016   큐슈대학 동적 구조생명과학 연구센터, 조교수

2016-현재   공주대학교 생명과학과 부교수

주요발표논문 (최근)

1. Kong S.-G., Shimada A., Kijima S.T., Hirose K., Katoh K., Ahn J., Higa T., Takano A., Nakamura Y., Suetsugu N., Kohda D., Uyeda T.Q.P., Wada M. (2020) CHLOROPLAST UNUSUAL POSITIONING1 is a new type of actin nucleation factor in plants. bioRxiv doi: https://doi.org/10.1101/2020.01.14.905984

2. Kim J.-Y., Ahn J., Bong H., Wada M., Kong S.-G. (2020) ACTIN2 functions in chloroplast photorelocation movement in Arabidopsis thaliana. Journal of Plant Biology 63(5): 379-389.

3. Yoon J. S., Lee S. H., Riu Y. S., Kong S.-G. (2019) Regulation of anthocyanin biosynthesis by light and nitrogen in Sarracenia purpurea. Journal of Life Science 29(10): 1055-1061.

4. Wada M., Kong S.-G. (2018) Actin-mediated movement of chloroplasts. Journal of Cell Science 131(2): pii: jcs210310.

5. Kong S.-G., Okajima K. (2016) Diverse photoreceptors and light responses in plants. Journal　 of Plant Research 129(2): 111-114.

6. Kong S.-G., Wada M. (2016) Molecular basis of chloroplast photorelocation movement. Journal of Plant Research 129(2): 159-166.