Cell polarity and tissue patterning in plants
Cell polarity and tissue patterning in plants
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植物的细胞极性和组织模式
DOI：
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发表时间：
1991
期刊：
影响因子：
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通讯作者：
T. Sachs
中科院分区：
文献类型：
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作者：
T. Sachs
细胞极化是发育事件沿着一个方向或一个方向的特化。这种极化必定是组织图案化的早期、重要阶段。方向的规范不能只发生在遗传系统的水平上，它必须表达许多细胞中事件的协调。细胞极化和已知激素生长素的运输之间存在正反馈关系：极性决定生长素运输的方向，而运输本身诱导新的和持续的极化。由于细胞极化逐渐增加，这种反馈导致沿着特定细胞的特定链的运输和相关细胞分化的管道化。最近的研究表明，相同的管道化流动也可能是细胞形状的重要决定因素。在原始胚胎区域，细胞生长沿着生长素从芽向根的流动定向。在发育后期，细胞通过生长来响应相同的信号流，可能会调整组织对信号流的能力。最后，伤口附近的流动中断导致相对无组织的愈伤组织的形成。愈伤组织的持续发育似乎需要细胞的参与，作为生长素和其他信号的来源和汇。总体情况表明，细胞模式可能是作为发育信号的首选通道、源和汇的细胞之间的竞争造成的。
Cell polarization is the specialization of developmental events along one orientation or one direction. Such polarization must be an early, essential stage of tissue patterning. The specification of orientation could not occur only at the level of the genetic system and it must express a coordination of events in many cells. There is a positive feedback relation between cell polarization and the transport of the known hormone auxin: polarity determines oriented auxin transport while transport itself induces both new and continued polarization. Since cell polarization increases gradually, this feedback leads to the canalization of transport – and of the associated cell differentiation – along defined strands of specialized cells. Recent work has shown that the same canalized flow can also be an important determinant of cell shape. In primordial, embryonic regions cell growth is oriented along the flow of auxin from the shoot towards the root. In later developmental stages the cells respond to the same flow by growing in girth, presumably adjusting the capacity of the tissues to the flow of signals. Finally, disrupted flow near wounds results in the development of relatively unorganized callus. Continued callus development appears to require the participation of the cells, as sources and sinks of auxin and other signals. The overall picture to emerge suggests that cell patterning can result from competition between cells acting as preferred channels, sources and sinks for developmental signals.