Department of Plant and Microbial Biology, University of California, Berkeley, California 94720
Plant Gene Expression Center, United States Department of Agriculture, Agricultural Research Service, Albany, California 94710.
Plant Physiol. 2019 Dec;181(4):1459-1467. doi: 10.1104/pp.19.00460. Epub 2019 Oct 10.
Plasmodesmata (PD) are essential for plant development, but little is known about their regulation. Several studies have linked PD transport to chloroplast-centered signaling networks, but the physiological significance of this connection remains unclear. Here, we show that PD transport is strongly regulated by light and the circadian clock. Light promotes PD transport during the day, but light is not sufficient to increase rates of PD transport at night, suggesting a circadian gating mechanism. Silencing expression of the core circadian clock gene, , allows light to strongly promote PD transport during subjective night, confirming that the canonical plant circadian clock controls the PD transport light response. We conclude that PD transport is dynamically regulated during the day/night cycle. Due to the many roles of PD in plant biology, this discovery has strong implications for plant development, physiology, and pathogenesis.
胞间连丝（PD）对于植物的生长发育是至关重要的，但人们对其调控机制却知之甚少。有几项研究已经将 PD 的运输与叶绿体为中心的信号网络联系起来，但这种联系的生理意义仍不清楚。在这里，我们表明 PD 的运输受到光和生物钟的强烈调控。光在白天促进 PD 的运输，但光不足以提高夜间 PD 运输的速度，这表明存在一个生物钟的门控机制。沉默核心生物钟基因的表达，允许光在主观夜间强烈促进 PD 的运输，这证实了经典的植物生物钟控制 PD 运输对光的反应。我们的结论是，PD 的运输在昼夜周期中是动态调控的。由于 PD 在植物生物学中的许多作用，这一发现对植物的发育、生理和发病机制都具有重要意义。
