Single-cell analysis of cis-regulatory elements.

Plant tissues and organs are composed of functionally discrete cell types that are all defined by the same genome sequence. Cell-type variation in part arises from differential accessibility of cis-regulatory elements that encode the blueprints for transcriptional programs underlying cell identity and function. Owing to technical limitations, the role of cis-regulatory elements in cell identity maintenance, differentiation, and functional specialization has remained relatively unexplored in plant systems. Single-cell profiling has emerged as a powerful tool to circumvent these past obstacles by enabling unbiased charting of transcriptional and cis-regulatory states at the resolution of individual cells. Here, we review state-of-the-art single-cell approaches and analytical frameworks that have paved the way for establishing the link between cellular phenotypic variation and cis-regulatory mechanisms in plants.