Photorespiration: regulation and new insights on the potential role of persulfidation.

Photorespiration has been considered a 'futile' cycle in C3 plants, necessary to detoxify and recycle the metabolites generated by the oxygenating activity of RUBISCO. However, several reports indicate that this metabolic route plays a fundamental role in plant metabolism and constitutes a very interesting topic of research. Many open questions still remain in regard to photorespiration. One of these questions is how the photorespiratory process is regulated in plants and what factors contribute to this regulation. In this paper, we summarize the progress made on this topic. Here, we review recent advances in the regulation of the photorespiratory pathway with a special focus on the transcriptional and posttranslational regulation of photorespiration and the interconnections of this process with nitrogen and sulfur metabolism. Recent findings on sulfide signaling and protein persulfidation are described.