Research focus

​The modification of proteins by ADP-ribosylation is an ancient mechanism to control cell cycle progression, DNA damage response and many other processes. It is catalyzed by the several classes of NAD+-metabolizing enzymes, among which poly(ADP-ribose) polymerase 1 (PARP1) in animals is the most known. The poly(ADP-ribose) glycohydrolase (PARG), ADP-ribose hydrolase and pyrophosphatase erase ADP-ribosylation.
The presence of the specific NAD+-binding amino acid signature suggests that the Arabidopsis genome contains genes for twelve proteins capable of ADP-ribosylation, and seven enzymes involved in the reversal of the modification. Plant PARP-like protein CEO/RCD protects yeast cells from drug-induced death, and in plants is a key regulator of responses to abiotic stress. Under stress conditions, improvements in the energy homeostasis can be achieved by the lowering of the APP and ZAP plant PARP gene activities, hence such adjustments to the plant energy metabolism are successfully exploited in the breeding of crop species for new varieties with a better stress tolerance (Babiychuk et al., 2004).  
 
Reduced carbon and the oxygen to burn it are predominantly provided by the photosynthesis, which makes it the most important process required to maintain animal life on the planet. In higher plants, it occurs in plastids. While photosynthesis is a key process for the growth and development of plants themselves, plastids do much more for the plant cell. Resolving old mysteries is one approach to gain a comprehensive understanding of the role of plastids in the plant life cycle. In the middle of the twentieth century, the German geneticist Michaelis proposed that an important role for plastids is a fixation of the post-zygotic interspecies isolation barriers through a mechanism known as nucleo-cytoplasmic incompatibility. The molecular details of the mechanism remained enigmatic until the process of RNA editing was found to be responsible for the incompatibility reactions between the nucleus and plastids of different species in Solanaceae (Schmitz-linneweber et al., 2005; Tillich et al., 2006). Another approach to better our knowledge of plastid biology is to search for processes and molecules outside plastids that nevertheless impact on photosynthesis or plastid biogenesis. Such experimentation confirmed the functional connections between plastids and mitochondria (Kushnir et al., 2001), and revealed a novel role for sterols in plastid biogenesis (Babiychuk et al., 2008).