Intracellular Signaling from Plastids to the Nucleus

Abstract

Signaling from chloroplasts or other plastids to the nucleus is part of the intracellular communication network of plants. Several signals originate in the plastids from processes like plastid gene expression, photosynthetic electron transport, or chlorophyll biosynthesis. In some cases, signaling compounds like reactive oxygen species or Mg-protoporphyrin are suggested to be involved in this process. Signaling leads to up- and down-regulation in the expression of certain nuclear genes. While the origins of signaling pathways in the plastids and the effect in the nucleus have been accessible to various experimental approaches, none of the signaling pathways has been completely elucidated. According to the present view, several signaling pathways are connected to a communication network in which light signals are also involved.