Raffinose Family Oligosaccharides: Crucial Regulators of Plant Development and Stress Responses

Raffinose family oligosaccharides (RFOs), the α-galactosyl derivatives of sucrose, are nearly ubiquitous in Plantae, and they have been demonstrated to play pivotal roles in regulating plant responses to various abiotic stresses. RFOs accumulate to high levels in plant kernels/fruits or vegetative parts and are commonly associated with storability and desiccation or cold tolerance. Recent studies have also revealed the regulatory roles of RFOs in seed germination, plant development, and biotic stress resistance. Here, we provide an overview of the metabolism, transport, and evolution of RFOs as well as their physiological importance in plants. Recent research highlights the general importance of RFOs in plant development and stress response.