Initiation and maintenance of plant stem cells in root and shoot apical meristems

Plant stem cells are a small group of cells with a self-renewal capacity and serve as a steady supply of precursor cells to form new differentiated tissues and organs in plants. Root stem cells and shoot stem cells, which are located in the root apical meristem and in the shoot apical meristem, respectively, play a critical role in plant longitudinal growth. These stem cells in shoot and root apical meristems remain as pluripotent state throughout the lifespan of the plant and control the growth and development of plants. The molecular mechanisms of initiation and maintenance of plant stem cells have been extensively investigated. In this review, we mainly discuss how the plant phytohormones, such as auxin and cytokinin, coordinate with the key transcription factors to regulate plant stem cell initiation and maintenance in root and shoot apical meristems. In addition, we highlight the common regulatory mechanisms of both root and shoot apical meristems.