초록 ▼

Ⅲ. 연구개발의 내용 및 범위
1. 식물 지상부(shoot system)에서 SHR, SCL23, SCR 전사조절인자 간 상호조절기작 규명 연구
○ 식물지상부에서 SHR의 기능분석
○ 식물지상부에서 SCL23의 기능분석
○ 식물지상부에서 SHR, SCR, SCL23 간 상호조절기작 분석
○ 식물지상부에서 SHR, SCR, SCL23과 식물호르몬과의 상호조절기작 규명
2. 식물 뿌리(root system)에서 SCL3-responsive 유전자 발굴 및 기능분석
○ 식물뿌리에서 SCL3-respo

Ⅲ. 연구개발의 내용 및 범위
1. 식물 지상부(shoot system)에서 SHR, SCL23, SCR 전사조절인자 간 상호조절기작 규명 연구
○ 식물지상부에서 SHR의 기능분석
○ 식물지상부에서 SCL23의 기능분석
○ 식물지상부에서 SHR, SCR, SCL23 간 상호조절기작 분석
○ 식물지상부에서 SHR, SCR, SCL23과 식물호르몬과의 상호조절기작 규명
2. 식물 뿌리(root system)에서 SCL3-responsive 유전자 발굴 및 기능분석
○ 식물뿌리에서 SCL3-responsive 유전자 발굴 및 기능분석
○ SCL3-responsive C2H2 Zinc Finger(CZF) 전사조절인자 기능분석
○ 식물뿌리에서 이들 전사조절인자들(SHR, SCR, SCL3, CZF)간 상호조절기작분석
○ 식물뿌리에서 이들 전사조절인자들(SHR, SCR, SCL3, CZF)과 식물호르몬과의 상호조절기작 규명(GA와 ABA 간 cross-talk을 중심으로)

Abstract ▼

The GRAS transcription regulators SHORT-ROOT (SHR) and SCARECROW (SCR) play important roles in ground tissue patterning and stem cell maintenance in roots of Arabidopsis thaliana. To date, it has been shown that SHR acts, mostly, together with its direct target SCR. However, recent studies suggest t

The GRAS transcription regulators SHORT-ROOT (SHR) and SCARECROW (SCR) play important roles in ground tissue patterning and stem cell maintenance in roots of Arabidopsis thaliana. To date, it has been shown that SHR acts, mostly, together with its direct target SCR. However, recent studies suggest the presence of SHR-dependent,SCR-independent pathways or vice versa. In this study, we provide a novel molecular interaction between SHR and SCARECROW-LIKE 23 (SCL23), the closest homolog of SCR. We found that both SHR and SCL23 are coexpressed in the shoot vasculature. Furthermore, transcription of SCL23 is regulated by SHR, which binds directly to the SCL23 promoter. The SHR binding to the SCL23 promoter depends on SCL23 itself, suggesting that SHR and SCL23 form a protein complex, like the SHR/SCR module in the root system. The genetic relationships between SHR, SCL23, and SCR suggest that SHR acts as a master regulator, and that both SCL23 and SCR, downstream of SHR, are partially redundant in the shoot system. Interestingly, overexpression of SCL23 reduces both SHR mRNA accumulation and SHR protein movement, completing a feedback loop, and results in retarded shoot growth and development. In addition, shr scl23 scr triple mutants show novel shoot phenotypes, including round leaves, extremely shortened petioles, and delayed flowering. The transcript levels of flowering-related genes are discernibly changed in the triple mutants. Taken together, the interplay of the master regulator, SHR, and its direct targets, SCL23 and SCR, controls growth and development in the Arabidopsis shoot system. Asymmetric cell division (ACD) plays an essential role in patterning processes during plant development. In roots of Arabidopsis thaliana, the interplay between SHORT-ROOT (SHR) and SCARECROW (SCR) transcription factors controls ground tissue patterning to generate the endodermis and cortex. Recent studies The plant hormone gibberellins (GA) play key roles in the control of these developmental processes by integrating dynamic change of external cues to the network of intrinsic programs. However, little is known about the molecular components that integrate the generic GA signaling into a specific cell/tissue to coordinate cell division and cell expansion. Here we report that Previously, we reported that GA signaling controls a formative division in the root endodermis and that SCARECROW-LIKE 3 (SCL3), acting as a tissue-specific integrator of GA signaling, controls the timing and extent of the formative division. To gain more insight on SCL3 function, we analyzed SCL3-responsive transcriptomes in the root with Affymetrix ATH1 microarrays. Of SCL3-responsive genes, we focus on a novel C2H2 zinc finger, named CZF. Expression of CZF is primarily observed in the root vasculature, and is upregulated by ABA. Furthermore, the ABI4 expression is modulated by CZF, and overexpression of CZF (35S::CZF) exhibits an ABA-sensitive phenotype. Interestingly, the CZF expression is upregulated by the loss of SHR function in the stele. This result suggests that the mobile SHR transcription factor regulates two direct targets, SCL3 in the endodermis and CZF in the stele, respectively. In our genetic analysis, we found that czf mutants suppress the delayed formative division in 35S::SCL3 roots. Taken together, our findings indicate that the mobile SHR transcription factor control the formative division in the Arabidopsis root, through the cross-talk between the two antagonistic hormone signaling pathways, GA and ABA.

목차 Contents

• 표 지 ... 1
• 제 출 문 ... 2
• 요 약 문 ... 3
• SUMMARY ... 22
• 목 차 ... 23
• 제1장 서 론 ... 24
• 제 1 절. 연구개발의 목적 및 필요성 ... 24
• 제 2 절. 연구개발의 범위 ... 24
• 제2장 국내외 기술개발 현황 ... 25
• 제1절. 국내 연구 현황 ... 25
• 제2절. 국외 연구 현황 ... 26
• 제3절. 국내·외 연구 현황 비교 및 필요 연구 분야 ... 27
• 제3장 연구개발수행 내용 및 결과 ... 28
• 제1절. 식물 지상부(shoot system)에서 SHR, SCL23, SCR 전사조절인자 간 상호조절기작 규명 연구 ... 28
• 제2절. 식물 뿌리(root system)에서 SCL3-responsive 유전자 발굴 및 기능분석 ... 37
• 제4장 연구개발목표 달성도 및 대외기여도 ... 44
• 제1절. 목표대비 달성도 ... 44
• 제2절. 대외기여도 ... 44
• 제2절. 정량적 성과 ... 45
• 제5장 연구개발결과의 활용계획 ... 46
• 제6장 연구개발과정에서 수집한 해외과학기술정보 ... 47
• 제7장 기타 중요 변동사항 ... 49
• 제8장 국가과학기술종합정보시스템에 등록한 연구장비 현황 ... 50
• 제9장 참고문헌 ... 51