Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK.
Plant Cell Environ. 2018 Aug;41(8):1742-1748. doi: 10.1111/pce.13137. Epub 2018 Feb 5.
Correct operation of the plant circadian clock is crucial for optimal growth and development. Recent evidence has shown that the plant clock is tissue specific and potentially hierarchical, implying that there are signalling mechanisms that can synchronise the clock in different tissues. Here, I have addressed the mechanism that allows the shoot and root clocks to be synchronised in light:dark cycles but not in continuous light. Luciferase imaging data from 2 different Arabidopsis accessions with 2 different markers show that the period of the root clock is much less sensitive to blue light than to red light. Decapitated roots were imaged either in darkness or with the top section of root tissue exposed to light. Exposure to red light reduced the period of the root tissue maintained in darkness, whereas exposure to blue light did not. The data indicate that light can be piped through root tissue to affect the circadian period of tissue in darkness. I propose that the synchronisation of shoots and roots in light:dark cycles is achieved by light piping from shoots to roots.
植物生物钟的正确运作对其最佳生长和发育至关重要。最近的证据表明，植物生物钟具有组织特异性和潜在的层级性，这意味着存在可以在不同组织中同步生物钟的信号机制。在这里，我研究了在光暗循环中使茎和根生物钟同步，但在连续光照下不能同步的机制。来自具有 2 种不同标记的 2 种不同拟南芥品系的荧光素酶成像数据表明，与红光相比，根生物钟的周期对蓝光的敏感性要低得多。将去顶的根在黑暗中或仅将根尖组织暴露在光下进行成像。暴露在红光下会降低在黑暗中维持的根组织的周期，而暴露在蓝光下则不会。这些数据表明，光可以通过根组织传输来影响在黑暗中组织的生物钟周期。我提出，通过从茎到根的光传输来实现光暗循环中茎和根的同步。
