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
ATP synthases in chloroplasts （cpATPase） and mitochondria （mtATPase） are responsible for ATP production during photosynthesis and oxidative phosphorylation, respectively. Both enzymes consist of two multi- subunit...ATP synthases in chloroplasts （cpATPase） and mitochondria （mtATPase） are responsible for ATP production during photosynthesis and oxidative phosphorylation, respectively. Both enzymes consist of two multi- subunit complexes, the membrane-bound coupling factor O and the soluble coupling factor 1. During cpATPase biosynthesis, several accessory factors facilitate subunit production and orchestrate complex assembly. Here, we describe a new auxiliary protein in Arabidopsis thaliana, which is required for cpATPase accumulation. AtCGLD11 （CONSERVED IN THE GREEN LINEAGE AND DIATOMS 11） is a protein without any known functional domain and shows dual localization to chloroplasts and mitochondria. Loss of AtCGLDll function results in reduced levels of cpATPase and impaired photosynthetic performance with lower rates of ATP synthesis. In yeast two-hybrid experiments, AtCGLD11 interacts with the 13 subunits of the cpATPase and mtATPase. Our results suggest that AtCGLD11 functions in F1 assembly during cpATPase biogenesis, while its role in mtATPase biosynthesis may not, or not yet, be essential.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.
文摘ATP synthases in chloroplasts （cpATPase） and mitochondria （mtATPase） are responsible for ATP production during photosynthesis and oxidative phosphorylation, respectively. Both enzymes consist of two multi- subunit complexes, the membrane-bound coupling factor O and the soluble coupling factor 1. During cpATPase biosynthesis, several accessory factors facilitate subunit production and orchestrate complex assembly. Here, we describe a new auxiliary protein in Arabidopsis thaliana, which is required for cpATPase accumulation. AtCGLD11 （CONSERVED IN THE GREEN LINEAGE AND DIATOMS 11） is a protein without any known functional domain and shows dual localization to chloroplasts and mitochondria. Loss of AtCGLDll function results in reduced levels of cpATPase and impaired photosynthetic performance with lower rates of ATP synthesis. In yeast two-hybrid experiments, AtCGLD11 interacts with the 13 subunits of the cpATPase and mtATPase. Our results suggest that AtCGLD11 functions in F1 assembly during cpATPase biogenesis, while its role in mtATPase biosynthesis may not, or not yet, be essential.
