Functional Screening of Plant Genes Suppressed Salt Sensitive Phenotype of Calcineurin Deficient Mutant through Yeast Complementation Analysis

국문 초록 (Abstract)

작물의 생산성 증가를 위해 염해 저항성 메커니즘을 이해하는 것이 중요하다. 식물의 염해 저항성에 관련된 유전자를 확보하기 위한 여러 가지의 선별방법이 개발되었다. 본 논문에서는 애기장대의 cDNA 라이브리를 염해 감수성 효모인 cnb 돌연변이체에 삽입하여 염해 감수성 표현형을 회복하는 콜로니를 선발하였다. 이 선별방법을 통하여 34종의 cnb 돌연변이체의 염해 감수성을 회복하는 콜로니를 선별하였으며, 염기서열분석을 통하여 CaS와 AtSUMO1, AtHB-12 등 9종의 유전자임을 확인하였다. 이들 유전자 중 CaS의 발현이 염해 저항성을 증가시키는 것과 염해 처리에 의해 CaS의 유전자의 발현이 증가되는 것을 확인하였다. CaS 발현억제 형질전환체는 100 mM 염처리에 의하여 뿌리생장이 저해되었다. 또한 150 mM 염처리에 의하여 CaS 발현억제 형질전환체의 잎에서 백화현상을 나타내었다. 이러한 결과를 통하여 CaS 유전자가 효모와 식물에서 염해 저항성에 중요한 유전자임을 증명하였다.

다국어 초록 (Multilingual Abstract)

Understanding salt tolerance mechanisms is important for the increase of crop yields, and so, several screening approaches were developed to identify plant genes which are involved in salt tolerance of plants. Here, we transformed the Arabidopsis cDNA library into a salt-sensitive calcineurin (CaN)-deficient (cnbΔ) yeast mutant and isolated the colonies which can suppress salt-sensitive phenotype of cnbΔ mutant. Through this functional complementation screen, a total of 34 colonies functionally suppressed the salt-sensitive phenotype of cnbΔ yeast cells, and sequencing analysis revealed that these are 9 genes, including CaS, AtSUMO1and AtHB-12. Among these genes, the ectopic expression of CaSgene increased salt tolerance in yeast, and CaStranscript was up-regulated under high salinity conditions. CaS-antisense transgenic plants showed reduced root elongation under 100 mM NaCl treatment compared to the wild type plant, which survived under 150 mM NaCl treatment, whereas CaS-antisense transgenic plant leaves turned yellow under 150 mM NaCl treatment. These results indicate that the expression of CaS gene is important for stress tolerance in yeast and plants.

목차 (Table of Contents)

• Introduction
• Materials and Methods
• Results
• Discussion
• References
• 초록

참고문헌 (Reference)

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