N-myristoyltransferase1 regulates biomass accumulation in cucumber (Cucumis sativus L.)1

Plant biomass is an important agronomic trait subjected to intense human selection for yield improvement. The underlying mechanism regulating biomass formation is currently gaining increasing attention, but still remains unexplored. In this study, we isolated a cucumber (Cucumis sativus L.) minicuke mutant with remarkably reduced biomass. The causative gene CsNMT1, a homologous to the Arabidopsis thaliana N-myristoyltransferase1, was identified. Our clustered regularly interspaced shot palindromic repeat-based genome editing confirmed the key role of CsNMT1 in biomass regulation. Multi-omics analyses integrating with metabolomic and transcriptomic analyses revealed the suppression of a very early step of lignin biosynthesis and the corresponding down-regulation of genes involved in the lignin biosynthesis in the minicikue mutant, suggesting an unexpected pathway to regulate biomass accumulation through lignin sink strength. Our findings demonstrate the function of NMT1 in regulating plant biomass and its potential application value for biomass improvement in cucurbits.