Functions of the nicotinamide adenine dinucleotide phosphate oxidase family in Ganoderma lucidum: an essential role in ganoderic acid biosynthesis regulation, hyphal branching, fruiting body development, and oxidative-stress resistance.
Ganoderma lucidum has drawn worldwide interest with regard to its secondary metabolism and pharmaceutical activity. However, the development of such research has been limited because of a lack of basic biological knowledge. Nicotinamide adenine dinucleotide phosphate oxidases (Nox) have recently been highlighted because of the many important biological roles in plants and animals; however, the exact functions of Nox are still not fully understood in fungi. In this study, we identified two Nox isoforms (NoxA and NoxB) and a regulator, NoxR. RNA interference was used, and silencing of the Nox isoforms and NoxR expression indicated a central role for these genes in hyphal branching, fruiting body development, reactive oxygen species (ROS) generation, ROS resistance and ganoderic acid biosynthesis regulation. Further mechanistic investigation revealed that Nox-generated ROS elevated cytosolic Ca(2+) levels by activating a plasma membrane Ca(2+) influx pathway, thereby inducing the Ca(2+) signal pathway to regulate ganoderic acid biosynthesis and hyphal branching. Importantly, our results highlight the Nox functions in signal crosstalk between ROS and Ca(2+), and these findings provide an excellent opportunity to identify the potential pathway linking ROS networks to calcium signalling in fungi and suggest that plants, animals and fungi share a conserved signal-crosstalk mechanism.
College of Life Sciences, Nanjing Agricultural University, Nanjing, China.
Dashuai
D
Mu
Chenyang
C
Li
Xuchen
X
Zhang
Xiongbiao
X
Li
Liang
L
Shi
Ang
A
Ren
Mingwen
M
Zhao
D001487:Basidiomycota / Q000201:enzymology* / Q000254:growth & development; D020013:Calcium Signaling; D048690:Fruiting Bodies, Fungal / Q000201:enzymology* / Q000254:growth & development; D005656:Fungal Proteins / Q000502:physiology*; D025301:Hyphae / Q000201:enzymology* / Q000254:growth & development; D019255:NADPH Oxidases / Q000502:physiology*; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism; D020940:Reishi; D014315:Triterpenes / Q000378:metabolism
D005656:Fungal Proteins; D017382:Reactive Oxygen Species; D014315:Triterpenes; C556862:ganoderic acid; D019255:NADPH Oxidases