Richardson Annis E, Hake Sarah
Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA.
USDA Plant Gene Expression Center, 800 Buchanan Street, Albany, CA 94710, USA.
Plants (Basel). 2018 Dec 25;8(1):4. doi: 10.3390/plants8010004.
Delineation between distinct populations of cells is essential for organ development. Boundary formation is necessary for the maintenance of pluripotent meristematic cells in the shoot apical meristem (SAM) and differentiation of developing organs. Boundaries form between the meristem and organs, as well as between organs and within organs. Much of the research into the boundary gene regulatory network (GRN) has been carried out in the eudicot model . This work has identified a dynamic network of hormone and gene interactions. Comparisons with other eudicot models, like tomato and pea, have shown key conserved nodes in the GRN and species-specific alterations, including the recruitment of the boundary GRN in leaf margin development. How boundaries are defined in monocots, and in particular the grass family which contains many of the world's staple food crops, is not clear. In this study, we review knowledge of the grass boundary GRN during vegetative development. We particularly focus on the development of a grass-specific within-organ boundary, the ligule, which directly impacts leaf architecture. We also consider how genome engineering and the use of natural diversity could be leveraged to influence key agronomic traits relative to leaf and plant architecture in the future, which is guided by knowledge of boundary GRNs.
区分不同的细胞群体对于器官发育至关重要。边界形成对于维持茎尖分生组织（SAM）中的多能分生细胞以及发育中器官的分化是必要的。边界在分生组织与器官之间形成，也在器官之间以及器官内部形成。对边界基因调控网络（GRN）的许多研究是在双子叶植物模型中进行的。这项工作确定了一个由激素和基因相互作用组成的动态网络。与其他双子叶植物模型（如番茄和豌豆）的比较表明，GRN中有关键的保守节点以及物种特异性变化，包括边界GRN在叶缘发育中的作用。单子叶植物，特别是包含许多世界主要粮食作物的禾本科植物中，边界是如何定义的尚不清楚。在本研究中，我们综述了营养发育过程中禾本科植物边界GRN的相关知识。我们特别关注禾本科植物特有的器官内部边界叶舌的发育，叶舌直接影响叶片结构。我们还考虑了未来如何利用基因组工程和自然多样性来影响与叶片和植株结构相关的关键农艺性状，这是以边界GRN的知识为指导的。
