An attempt is reported to link changes in thylakoid lipid composition with the electron-transport and ATP-formation capability of the chloroplast. The observation that the monogalactolipid : phosphatid-ratio (M GDG/PL) of leaf sections shows a linear correlation with the P/2e value of simul­ taneously isolated Jensen-Bassham plastids was followed up experimentally for an in vitro plastid system...

The evolution of oxygenic photosynthesis in the ancestors of present-day cyanobacteria transformed the biosphere of our planet (Blankenship 1994; ReyesPrieto et al. 2007). This landmark event was also an essential prerequisite for the evolution of photosynthetic eukaryotes. Plastids, or chloroplasts, are the lightgathering organelles of algae and plants whose origin can be traced back to cyanob...

Stromules are dynamic thin protrusions of membrane envelope from plant cell plastids. Despite considerable progress in understanding the importance of certain cytoskeleton elements and motor proteins for stromule maintenance, their function within the cell has yet to be unraveled. Several viruses cause a remodulation of plastid structures and stromule biogenesis within their host plants. For RN...

Riboswitches are natural RNA sensors that regulate gene expression in response to ligand binding. Riboswitches have been identified in prokaryotes and eukaryotes but are unknown in organelles (mitochondria and plastids). Here we have tested the possibility to engineer riboswitches for plastids (chloroplasts), a genetic system that largely relies on translational control of gene expression. To t...

Abstract Variable trace metal concentrations in the Precambrian ocean were closely linked to oxygen availability, although less is known about drivers of seawater chemistry after spread complex life into Phanerozoic eon. A major phytoplankton succession took place at transition from Palaeozoic Mesozoic era (~250 Myr ago), an dominated by green Archaeplastida secondary endosymbiotic algae with r...

The chloroplast division machinery is a mixture of a stromal FtsZ-based complex descended from a cyanobacterial ancestor of chloroplasts and a cytosolic dynamin-related protein (DRP) 5B-based complex derived from the eukaryotic host. Molecular genetic studies have shown that each component of the division machinery is normally essential for normal chloroplast division. However, several exceptio...

This report gives a comparison of the specificity of phosphate translocators in various plastids. Whereas the phosphate translocator of the C(3) plant spinach mediates a counter exchange between inorganic phosphate, dihydroxyacetone phosphate, and 3-phosphoglycerate, the phosphate translocators in chloroplasts from C(4) and CAM plants transport phosphoenolpyruvate in addition to the above menti...

Plastid stromules are membrane-bound protrusions of the plastid envelope that contain soluble stroma. Stromules are often found connecting plastids within a cell and fluorescence recovery after photobleaching (FRAP) experiments have demonstrated that green fluorescent protein (GFP) can move between plastids via these connections. In this report, the ability of endogenous plastid proteins to tra...

Plastids are organelles present in photosynthetic and nonphotosynthetic plant tissues. While it is well known that thioredoxin-dependent redox regulation is essential for leaf chloroplast function, little is known of the redox regulation in plastids of nonphotosynthetic tissues, which cannot use light as a direct source of reducing power. Thus, the question remains whether redox regulation oper...

Acetyl-coenzyme A carboxylase (ACCase) occurs in at least two forms in rapeseed (Brassica napus): a homomeric (HO) and presumably cytosolic isozyme and a heteromeric, plastidial isozyme. We investigated whether the HO-ACCase of Arabidopsis can be targeted to plastids of B. napus seeds. A chloroplast transit peptide and the napin promoter were fused to the Arabidopsis ACC1 gene and transformed i...