All members of the YidC/Oxal/Alb3 protein family are evolutionarily conserved and appear to function in membrane protein integration and protein complex stabilization. Here, we report on a second thylakoidal isoform o...All members of the YidC/Oxal/Alb3 protein family are evolutionarily conserved and appear to function in membrane protein integration and protein complex stabilization. Here, we report on a second thylakoidal isoform of Alb3, named Alb4. Analysis of Arabidopsis knockout mutant lines shows that AIb4 is required in assembly and/or stability of the CF1CF0-ATP synthase （ATPase）. alb4 mutant lines not only have reduced steady-state levels of ATPase subunits, but also their assembly into high-molecular-mass complexes is altered, leading to a reduction of ATP synthesis in the mutants. Moreover, we show that Alb4 but not AIb3 physically interacts with the subunits CF1β and CF0ll. Summarizing, the data indicate that AIb4 functions to stabilize or promote assembly of CF1 during its attachment to the membrane-embedded CF0 part.展开更多
Subunit interactions of the chloroplast F0F1-ATP synthase were studied using the yeast two-hybrid sys-tem. The coding sequences of all the nine subunits of spinach chloroplast ATP synthase were cloned in two-hybrid ve...Subunit interactions of the chloroplast F0F1-ATP synthase were studied using the yeast two-hybrid sys-tem. The coding sequences of all the nine subunits of spinach chloroplast ATP synthase were cloned in two-hybrid vectors. The vectors were transformed into the yeast strains HF7c and SFY526 by various pairwise combinations, and the protein interactions were analyzed by measuring the yeast growth on minimal SD medium without serine, lucine and histidine. Interactions of γ subunit with wild type or two truncated mutants of ε sununit, ε△N21 and ε△C45, which lose their abilities to inhibit the ATP hydrolysis, were also detected by in vitro and in vivo binding assay. The present results are largely accordant to the common structure model of F0F1-ATP synthase. Different from that in the E. coli F0F1-ATP synthase, the δ subunit of chloroplast ATP synthase could interact with β. γ, ε and all the CF0 subunits in the two-hybrid system. These results suggested that though the chloroplast ATP synthase展开更多
文摘All members of the YidC/Oxal/Alb3 protein family are evolutionarily conserved and appear to function in membrane protein integration and protein complex stabilization. Here, we report on a second thylakoidal isoform of Alb3, named Alb4. Analysis of Arabidopsis knockout mutant lines shows that AIb4 is required in assembly and/or stability of the CF1CF0-ATP synthase （ATPase）. alb4 mutant lines not only have reduced steady-state levels of ATPase subunits, but also their assembly into high-molecular-mass complexes is altered, leading to a reduction of ATP synthesis in the mutants. Moreover, we show that Alb4 but not AIb3 physically interacts with the subunits CF1β and CF0ll. Summarizing, the data indicate that AIb4 functions to stabilize or promote assembly of CF1 during its attachment to the membrane-embedded CF0 part.
基金This work was supported by theState Key Basic Research and Development Plan (Grant No. G1998010100) the National Natural Science Foundation of China (Grant No. 39730040).
文摘Subunit interactions of the chloroplast F0F1-ATP synthase were studied using the yeast two-hybrid sys-tem. The coding sequences of all the nine subunits of spinach chloroplast ATP synthase were cloned in two-hybrid vectors. The vectors were transformed into the yeast strains HF7c and SFY526 by various pairwise combinations, and the protein interactions were analyzed by measuring the yeast growth on minimal SD medium without serine, lucine and histidine. Interactions of γ subunit with wild type or two truncated mutants of ε sununit, ε△N21 and ε△C45, which lose their abilities to inhibit the ATP hydrolysis, were also detected by in vitro and in vivo binding assay. The present results are largely accordant to the common structure model of F0F1-ATP synthase. Different from that in the E. coli F0F1-ATP synthase, the δ subunit of chloroplast ATP synthase could interact with β. γ, ε and all the CF0 subunits in the two-hybrid system. These results suggested that though the chloroplast ATP synthase
