Shoot at Site: Advancing in planta transformation, regeneration and gene-editing through a cascade of wounding-mediated developmental regulators

Abstract

Developing transgenic and/or gene-edited plants largely depends on tedious, lengthy, and costly in vitro regeneration protocols. While plants have remarkable regeneration ability, not all species, genotypes or even explants exhibit the same transformation and regeneration potential under in vitro conditions. To tackle this bottleneck, we have developed a seamless and user-friendly system to induce transgenic and gene-edited de novo meristems via a synthetic cascade comprising a wound-induced regeneration pathway, plant developmental regulators (DRs) and gene-editing reagents. WOUND INDUCED DEDIFFERENTIATION 1 (WIND1) is used as a transcriptional regulator to control the expression of various DR genes through ENHANCER OF SHOOT REGENERATION 1 (ESR1) promoter. This cascade was strategically applied in planta to the non-meristematic internode of N. benthamiana to induce meristematic activity and regenerate de novo shoots with knock-out mutations of the phytoene desaturase (PDS) gene. This synthetic toolkit was further applied successfully to tomato and soybean. This methodology offers a transformative approach to overcome barriers in plant biotechnology, potentially accelerating the generation of transgenic and gene-edited plants without reliance on conventional tissue-culture intermediates.