Reinhardt Didier, Pesce Eva-Rachele, Stieger Pia, Mandel Therese, Baltensperger Kurt, Bennett Malcolm, Traas Jan, Friml Jirí, Kuhlemeier Cris
Institute of Plant Sciences, University of Bern, Switzerland.
Nature. 2003 Nov 20;426(6964):255-60. doi: 10.1038/nature02081.
The regular arrangement of leaves around a plant's stem, called phyllotaxis, has for centuries attracted the attention of philosophers, mathematicians and natural scientists; however, to date, studies of phyllotaxis have been largely theoretical. Leaves and flowers are formed from the shoot apical meristem, triggered by the plant hormone auxin. Auxin is transported through plant tissues by specific cellular influx and efflux carrier proteins. Here we show that proteins involved in auxin transport regulate phyllotaxis. Our data indicate that auxin is transported upwards into the meristem through the epidermis and the outermost meristem cell layer. Existing leaf primordia act as sinks, redistributing auxin and creating its heterogeneous distribution in the meristem. Auxin accumulation occurs only at certain minimal distances from existing primordia, defining the position of future primordia. This model for phyllotaxis accounts for its reiterative nature, as well as its regularity and stability.
植物茎周围叶子的规则排列,即叶序,几个世纪以来一直吸引着哲学家、数学家和自然科学家的关注;然而,迄今为止,叶序研究在很大程度上仍停留在理论层面。叶子和花朵由茎尖分生组织形成,这一过程由植物激素生长素触发。生长素通过特定的细胞内流和外流载体蛋白在植物组织中运输。我们在此表明,参与生长素运输的蛋白质调控叶序。我们的数据表明,生长素通过表皮和最外层分生组织细胞层向上运输到分生组织中。现有的叶原基充当库,重新分配生长素并在分生组织中形成其不均匀分布。生长素仅在距现有原基一定最小距离处积累,从而确定未来原基的位置。这种叶序模型解释了其重复性、规律性和稳定性。