The role of nitric oxide in plant biology: current insights and future perspectives

Abstract

Nitric oxide (NO) is a redox-active gaseous signal uniformly present in eukaryotes, but its formation, signalling, and effects are specific within the plant kingdom in several aspects. NO synthesis in algae proceeds by mechanisms similar to that in mammals, but there are different pathways in higher plants. Beyond synthesis, the regulatory processes to maintain steady-state NO levels are also integral for the projection of NO function. As a key redox molecule, NO exhibits a number of pivotal molecular interactions, for example with reactive oxygen species, hydrogen sulfide, and calcium, with these molecular interplays largely underpinning NO bioactivity. In this context, NO has emerged as a key regulator in plant growth, development, and environmental interactions. In this special issue, a collection of reviews discusses the current state-of-the-art and possible future directions related to the biology and chemistry of plant NO function.