RNA-Seq based phylogeny recapitulates previous phylogeny of the genus Flaveria (Asteraceae) with some modifications.

Background: The genus Flaveria has been extensively used as a model to study the evolution of C4 photosynthesis as it contains C3 and C4 species as well as a number of species that exhibit intermediate types of photosynthesis. The current phylogenetic tree of the genus Flaveria contains 21 of the 23 known Flaveria species and has been previously constructed using a combination of morphological data and three non-coding DNA sequences (nuclear encoded ETS, ITS and chloroplast encoded trnL-F).

Results: Here we developed a new strategy to update the phylogenetic tree of 16 Flaveria species based on RNA-Seq data.

The role of photorespiration during the evolution of C4 photosynthesis in the genus Flaveria.

C4 photosynthesis represents a most remarkable case of convergent evolution of a complex trait, which includes the reprogramming of the expression patterns of thousands of genes. Anatomical, physiological, and phylogenetic and analyses as well as computational modeling indicate that the establishment of a photorespiratory carbon pump (termed C2 photosynthesis) is a prerequisite for the evolution of C4. However, a mechanistic model explaining the tight connection between the evolution of C4 and C2 photosynthesis is currently lacking.

Evolution of the Phosphoenolpyruvate Carboxylase Protein Kinase Family in C3 and C4 Flaveria spp.

The key enzyme for C photosynthesis, Phosphoenolpyruvate Carboxylase (PEPC), evolved from nonphotosynthetic PEPC found in C ancestors. In all plants, PEPC is phosphorylated by Phosphoenolpyruvate Carboxylase Protein Kinase (PPCK). However, differences in the phosphorylation pattern exist among plants with these photosynthetic types, and it is still not clear if they are due to interspecies differences or depend on photosynthetic type.

Preclinical trials in autosomal dominant AD: implementation of the DIAN-TU trial.

The Dominantly Inherited Alzheimer's Network Trials Unit (DIAN-TU) was formed to direct the design and management of interventional therapeutic trials of international DIAN and autosomal dominant Alzheimer's disease (ADAD) participants. The goal of the DIAN-TU is to implement safe trials that have the highest likelihood of success while advancing scientific understanding of these diseases and clinical effects of proposed therapies. The DIAN-TU has launched a trial design that leverages the existing infrastructure of the ongoing DIAN observational study, takes advantage of a variety of drug targets, incorporates the latest results of biomarker and cognitive data collected during the observational study, and implements biomarkers measuring Alzheimer's disease (AD) biological processes to improve the efficiency of trial design.

Evolution of C4 photosynthesis in the genus flaveria: establishment of a photorespiratory CO2 pump.

C4 photosynthesis is nature's most efficient answer to the dual activity of ribulose-1,5-bisphosphate carboxylase/oxygenase and the resulting loss of CO(2) by photorespiration. Gly decarboxylase (GDC) is the key component of photorespiratory CO(2) release in plants and is active in all photosynthetic tissues of C(3) plants, but only in the bundle sheath cells of C(4) plants. The restriction of GDC to the bundle sheath is assumed to be an essential and early step in the evolution of C(4) photosynthesis, leading to a photorespiratory CO(2) concentrating mechanism.