Dormancy by communication shutdown Trees become dormant in winter, with encapsulated buds protected against harsh conditions. Tylewicz et al. found that, as the days get shorter, communication channels between cells in aspen trees shut down. The blocked plasmodesmata sequester the dormant meristems from growth signals. Growth-promoting signals can be turned on and off relatively rapidly, but the closed plasmodesmata are not so nimble. Thus, despite the occasional sunny day, the trees stay dormant until spring. Science, this issue p. 212 Aspen trees go dormant in winter because plasmodesmata, which would otherwise convey growth-promoting signals, shut down communication. In temperate and boreal ecosystems, seasonal cycles of growth and dormancy allow perennial plants to adapt to winter conditions. We show, in hybrid aspen trees, that photoperiodic regulation of dormancy is mechanistically distinct from autumnal growth cessation. Dormancy sets in when symplastic intercellular communication through plasmodesmata is blocked by a process dependent on the phytohormone abscisic acid. The communication blockage prevents growth-promoting signals from accessing the meristem. Thus, precocious growth is disallowed during dormancy. The dormant period, which supports robust survival of the aspen tree in winter, is due to loss of access to growth-promoting signals.

中文翻译：

---

季节性生长的光周期控制是由作用于细胞间通讯的 ABA 介导的

通信关闭导致休眠 树木在冬季休眠，封装的芽可抵御恶劣条件。泰莱维茨等人。发现，随着时间的推移，白杨树细胞之间的通信通道关闭。被阻断的胞间连丝将休眠的分生组织与生长信号隔离。促进生长的信号可以相对快速地打开和关闭，但闭合的胞间连丝就没有那么灵活了。因此，尽管偶尔会有晴天，但树木会一直休眠到春天。科学，这个问题 p。212 白杨树在冬天进入休眠状态，因为胞间连丝（否则会传递促进生长的信号）关闭了通讯。在温带和寒带生态系统中，生长和休眠的季节性循环使多年生植物能够适应冬季条件。我们在杂交白杨树中展示，休眠的光周期调节在机制上与秋季生长停止不同。当通过胞间连丝进行的共生细胞间通讯被依赖于植物激素脱落酸的过程阻断时，休眠就开始了。通讯障碍阻止促进生长的信号进入分生组织。因此，在休眠期间不允许早熟生长。冬眠期支持白杨树在冬季茁壮成长，这是由于无法获得促进生长的信号。因此，在休眠期间不允许早熟生长。冬眠期支持白杨树在冬季茁壮成长，这是由于无法获得促进生长的信号。因此，在休眠期间不允许早熟生长。冬眠期支持白杨树在冬季茁壮成长，这是由于无法获得促进生长的信号。