Biochemical Changes of Protein during the Senescence of Tobacco Leaf

담배잎의 노화과정에 따른 단백질의 생화학적 변화

This experiment was conducted to obtain basic information of biochemical changes in the process of senescence by measuring the total RNA, protein, protease activity and electrophoretic pattern of protein in tobacco plant. The content of soluble protein increased by 15 days after leaf emergence and its level was not changed from 15 to 35 days after leaf emergence. The content of total RNA showed a maximum value at 15 days after leaf emergence and then decreased rapidly until 30 days after leaf emergence. The activity of protease of neutral fraction was higher than that of acidic fraction and rapidly increased up to the end of senescence after 50 days after leaf emergence. According to the analysis of electrophoresis, polypeptide band of 61kd was developed after 35 days after leaf emergence and increased by the end of senescence.

담배 생육단계별 RNA, protease 활성도와 단백질 패턴의 변화를 파악하여 노화가 진행되는 과정에서 생리 ㆍ생화학적인 변화의 기초자료를 얻고자 본 실험을 수행하였으며 결과는 다음과 같다. 가용성 단백질 함량은 출엽 후 15일까지 증가하여 출엽 후 35일까지 일정하게 유지하였다. 총 RNA 함량은 출엽 후 15일에 가장 높았으며 출엽후 30일까지 급격한 감소를 보였다. Protease 활성 변화는 중성 protease (pH 7.8)가 활성이 높았으며 노화말기인 출엽 후 50일부터 갑자기 증가하였다. 전기영동 패턴은 큰 변화가 없었으나 61.0kd의 polypeptide은 출엽 후 35일부터 생성되어 노화말기까지 증가하였다.