ABSTRACT
Photosynthesis-related proteins and PSII functions of Jatropha curcas seedlings under cold stress were studied using proteomic and chlorophyll fluorescence approaches. The results of chlorophyll fluorescence measurement indicated that electron transport flux per reaction center (ET(o)/RC) and performance index (PI(ABS)) were relatively sensitive to low temperature, especially at early stage of cold stress. The increase in O-J phase and decrease in J-I phase of chlorophyll fluorescence transient indicated a protection mechanism of J. curcas to photoinhibition at early stage of cold stress. Eight photosynthesis-related proteins significantly changed during cold stress were identified using liquid chromatography MS/MS. Results of correlation analyses between photosynthesis-related proteins and chlorophyll fluorescence parameters indicated that (1) ATP synthase and Rieske FeS protein were significantly correlated with electron transport of reaction center in PSII; (2) precursor for 33-kDa protein was positively correlated with fluorescence quenching of the O-J and J-I phases and PI(ABS) during cold stress, which implies that it might be related to multiple process in PSII; (3) contrary correlations were found between F(J) - F(o) and two enzymes in the Calvin cycle, and the relations between these proteins and PSII function were unclear. The combined study using proteomic approaches and chlorophyll fluorescence measurements indicated that the early-stage (0-12 h) acclimation of PSII and the late-stage (after 24 h) H(2)O(2) scavenging might be involved in the cold response mechanisms of J. curcas seedlings.
Subject(s)
Chlorophyll/metabolism , Cold Temperature , Jatropha/metabolism , Photosynthesis/physiology , Seedlings/metabolism , Chlorophyll/chemistry , Chromatography, Liquid , Electrophoresis, Gel, Two-Dimensional , Fluorescence , Gene Expression Regulation, Plant , Jatropha/genetics , Photosystem II Protein Complex/genetics , Photosystem II Protein Complex/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Seedlings/genetics , Tandem Mass SpectrometryABSTRACT
OBJECTIVE: To study the effect of endophytic fungi. METHOD: A. formosanus, harvested after having been cultured for age, statistics were taken, fresh weight and dry weight were gained, and enzyme activities of chitinase, beta-1,3-glucase, phenylalanine ammonia-lyase and polyphenoloxidase were determined. RESULT: The survial rates of A. formosanus inoculated with endophytic fungi was 100%. The effect of fungi on fresh weight was very significant (P < 0.01). The effect of fungi on dry weight was significant (P > 0.05). The four enzyme activities were enhanced by endophytic fungi, comparision with the controls. CONCLUSION: Survial rates of A. formosanus can be increased by using endophytic fungi in vitro culture.
