Hydrogen sulfide promotes lateral root formation in peach through persulfidation of <scp>SnRK1α</scp> kinase
Xuelian Wu, Anqi Du, Jiahui Liang, Zhe Wang, Yuansong Xiao, Futian Peng
Abstract
Summary Root development is crucial for the growth and yield of horticultural crops. Hydrogen sulfide (H 2 S), an important gasotransmitter, has been shown to regulate lateral root (LR) formation in plants, including peach ( Prunus persica ). However, its specific regulatory mechanism remains largely unclear. Here, we show that the energy/metabolic sensor SUCROSE NON‐FERMENTING RELATED KINASE 1 (SnRK1) mediates the control of peach LR growth by H 2 S. PpSnRK1 activity in peach roots is enhanced with H 2 S to promote LR generation. Cys419, Cys430 and Cys505 residues in the catalytic α‐subunit of PpSnRK1 are modified by H 2 S persulfidation. Reduced persulfidation inhibits the H 2 S‐induced PpSnRK1 activity. Mutating Cys419 and Cys430 of PpSnRK1α severely impedes H 2 S‐promoted LR formation. LATERAL ORGAN BOUNDARIES DOMAIN 16 (LBD16) is a transcription factor essential for LR initiation. Further evidence shows that PpSnRK1α interacts with PpLBD16 in the nucleus, thereby enhancing the transcription of LR development‐related genes PpCNGC1 ( CYCLIC NUCLEOTIDE‐GATED ION CHANNEL 1 ) and PpEXPB2 ( EXPANSIN‐B2 ). In peach roots, transcription of these two genes is markedly up‐regulated by H 2 S‐induced PpSnRK1 activity. Silencing of PpLBD16 , PpEXPB2 or PpCNGC1 significantly reduces exogenous H 2 S‐induced LR formation. In situ hybridization analysis shows that they are strongly expressed in peach LR primordia along with PpSnRK1α . Our data reveal an interaction between H 2 S signal and SnRK1 kinase, providing mechanistic insights into the shaping of agronomically important root systems.