植物学报
植物學報
식물학보
ACTA BOTANICA SINICA
2003年
9期
1076-1083
,共8页
王妮妍%蒋德安%洪健%张峰%翁晓燕
王妮妍%蔣德安%洪健%張峰%翁曉燕
왕니연%장덕안%홍건%장봉%옹효연
日变化%Rubisco%Rubisco活化酶(RCA)%定位%叶绿体%线粒体
日變化%Rubisco%Rubisco活化酶(RCA)%定位%葉綠體%線粒體
일변화%Rubisco%Rubisco활화매(RCA)%정위%협록체%선립체
diurnal changes%Rubisco%Rubisco activase%location%chloroplast%mitochondria
采用免疫胶体金标记电镜技术对水稻(0ryza sativa subsp.indica cv.浙农952)叶片中的Rubisco及其活化酶(RCA)进行细胞器定位和定量,同时用免疫扩散法进行叶片含量分析,研究了这两种酶含量及活力的日变化.结果表明Rubisco主要分布于叶绿体,RCA分布于叶绿体和线粒体中;光合速率(Pn)、Rubisco初始活力和RCA活力与光合日变化密切相关;在光照最强的13时,出现光合"午休",叶绿体中Rubisco的密度有一定程度降低,而全叶的总Rubisco保持稳定,Rubisco初始活力也有明显的"午休",这意味着体内Rubisco的活力除受RCA调节外,可能还与叶绿体中Rubisco的分布有关.RCA活力变化与叶绿体中RCA含量变化较为一致,表明RCA在叶绿体中的分布对调节其本身活力和Rubisco活性有重要作用.
採用免疫膠體金標記電鏡技術對水稻(0ryza sativa subsp.indica cv.浙農952)葉片中的Rubisco及其活化酶(RCA)進行細胞器定位和定量,同時用免疫擴散法進行葉片含量分析,研究瞭這兩種酶含量及活力的日變化.結果錶明Rubisco主要分佈于葉綠體,RCA分佈于葉綠體和線粒體中;光閤速率(Pn)、Rubisco初始活力和RCA活力與光閤日變化密切相關;在光照最彊的13時,齣現光閤"午休",葉綠體中Rubisco的密度有一定程度降低,而全葉的總Rubisco保持穩定,Rubisco初始活力也有明顯的"午休",這意味著體內Rubisco的活力除受RCA調節外,可能還與葉綠體中Rubisco的分佈有關.RCA活力變化與葉綠體中RCA含量變化較為一緻,錶明RCA在葉綠體中的分佈對調節其本身活力和Rubisco活性有重要作用.
채용면역효체금표기전경기술대수도(0ryza sativa subsp.indica cv.절농952)협편중적Rubisco급기활화매(RCA)진행세포기정위화정량,동시용면역확산법진행협편함량분석,연구료저량충매함량급활력적일변화.결과표명Rubisco주요분포우협록체,RCA분포우협록체화선립체중;광합속솔(Pn)、Rubisco초시활력화RCA활력여광합일변화밀절상관;재광조최강적13시,출현광합"오휴",협록체중Rubisco적밀도유일정정도강저,이전협적총Rubisco보지은정,Rubisco초시활력야유명현적"오휴",저의미착체내Rubisco적활력제수RCA조절외,가능환여협록체중Rubisco적분포유관.RCA활력변화여협록체중RCA함량변화교위일치,표명RCA재협록체중적분포대조절기본신활력화Rubisco활성유중요작용.
The cellular localization of Rubisco and Rubisco activase (RCA) in rice (Oryza sativa subsp.indica cv. Zhenong 952) leaf was investigated with immunogold-labeled electron microscope techniques onthe basis of determining the diurnal changes of photosynthetic rate (Pn), Rubisco and RCA activities, andquantifying two enzyme contents in the leaf with immuno-diffusion method in order to understand whyRCA activity decreased in the midday when its contents was high. The results showed that Rubisco mainlywas located in chloroplast, and RCA were found both in chloroplast and mitochondria. The lowering ofRubisco in chloroplast as well as Rubisco activity at noon could be one of good reasons to explain thephotosynthetic midday depression in leaf. The density of RCA in chloroplast reached the maximum at14:00 and a valley at 11:00. The result much coincided with the activity of RCA in leaf. In mitochondria, thedensity of RCA changed abruptly in one day with the highest at 13:00 and it can well elucidate why theactivities of Rubisco declined at noon when its amount was increasing. Therefore the cellular localizationand/or distribution of Rubisco and RCA during a day is more important for Pn, Rubisco and RCA activities.