Reconstruction of lateral root formation through single-cell RNA sequencing reveals order of tissue

• 作 者: Laura Serrano-Ron Pablo Perez-Garcia Alvaro Sanchez-Corrionero Inmaculada Gude Javier Cabrera Pui-Leng Ip Kenneth D.Birnbaum Miguel A.Moreno-Risueno
• 机 构: Centro de Biotecnología y Genómica de Plantas,Universidad Politécnica de Madrid(UPM)-Instituto Nacio
• 出 处: 分子植物（英文版）
• 发表日期: 2021年8期
• 关键词: organogenesis patterning stem cells single-cell RNA-seq cell fate regeneration

Postembryonic organogenesis is critical for plant development.Underground,lateral roots(LRs)form the bulk of mature root systems,yet the ontogeny of the LR primordium(LRP)is not clear.In this study,we per-formed the single-cell RNA sequencing through the first four stages of LR formation in Arabidopsis.Our analysis led to a model in which a single group of precursor cells,with a cell identity different from their peri-cycle origins,rapidly reprograms and splits into a mixed ground tissue/stem cell niche fate and a vascular precursor fate.The ground tissue and stem cell niche fates soon separate and a subset of more specialized vascular cells form sucrose transporting phloem cells that appear to connect to the primary root.We did not detect cells resembling epidermis or root cap,suggesting that outer tissues may form later,preceding LR emergence.At this stage,some remaining initial precursor cells form the primordium flanks,while the rest create a reservoir of pluripotent cells that are able to replace the LR if damaged.Laser ablation of the central and lateral LRP regions showed that remaining cells restart the sequence of tissue initiation to form a LR.Collectively,our study reveals an ontological hierarchy for LR formation with an early and sequential split of main root tissues and stem cells.