The past decades have witnessed the discovery of several gaseous signaling molecules in plants, including nitric oxide (NO), carbon monoxide (CO), hydrogen sulfide (H₂S), and methane (CH₄). These gasotransmitters (GTs) are endogenously synthesized in plant cells and participate in a variety of developmental processes and stress responses. Heavy metals (HMs) are one of the most widespread environmental cues that cause hazardous effects in plants and raise wide safety concerns. The involvement of GTs in the plant responses to HM has been demonstrated; however, our understanding of their exact roles and mechanisms in this area remains very fragmented. In this review, we provide an overview of the recent advances in the biosynthesis and regulation of each of the four GTs, their roles and mechanisms in plant HM uptake, accumulation, and detoxification, and the crosstalk between various GTs related to HM. Some reports on the negative roles of GTs on plant HM responses are also discussed. Certain important future directions for more in-depth studies are proposed based on the current understanding. Overall, this review provides a collection of rare information that helps to elucidate the regulation and functions of GTs in plant HM responses. This subject is of significant importance in the strategies of the agricultural efforts to reduce the risks associated with HMs by manipulating GTs.

过去几十年见证了植物中几种气态信号分子的发现，包括一氧化氮（NO），一氧化碳（CO），硫化氢（H ₂ S）和甲烷（CH ₄）。这些气体递质（GTs）是在植物细胞中内源性合成的，并参与多种发育过程和胁迫反应。重金属（HMs）是最广泛的环境提示之一，在工厂中造成有害影响并引起广泛的安全隐患。已经证明了GTs参与了植物对HM的反应。但是，我们对它们在这一领域的确切作用和机制的理解仍然是零碎的。在这篇综述中，我们概述了四个GT的生物合成和调控的最新进展，它们在植物HM吸收，积累和解毒中的作用和机制，以及与HM相关的各种GT之间的串扰。还讨论了一些有关GT对植物HM反应的负面作用的报道。根据当前的理解，提出了一些更深入研究的重要未来方向。总体而言，本综述提供了一些稀有信息，有助于阐明GT在植物HM反应中的调控和功能。在通过操纵GT来减少与HM相关的风险的农业努力策略中，该主题具有重要意义。