Haus Miranda J, Li Mao, Chitwood Daniel H, Jacobs Thomas W
Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, United States.
Department of Plant Biology, Michigan State University, East Lansing, MI, United States.
Front Plant Sci. 2018 Nov 30;9:1714. doi: 10.3389/fpls.2018.01714. eCollection 2018.
Stomata control water loss and carbon dioxide uptake by both altering pore aperture and developmental patterning. Stomatal patterning is regulated by environmental factors including atmospheric carbon dioxide ([CO]), which is increasing globally at an unprecedented rate. Mature leaves are known to convey developmental cues to immature leaves in response to [CO], but the developmental mechanisms are unknown. To characterize changes in stomatal patterning resulting from signals moving from mature to developing leaves, we constructed a dual-chamber growth system in which rosette and cauline leaves of were subjected to differing [CO]. Young rosette tissue was found to adjust stomatal index (SI, the proportion of stomata to total cell number) in response to both the current environment and the environment experienced by mature rosette tissue, whereas cauline leaves appear to be insensitive to [CO] treatment. It is likely that cauline leaves and cotyledons deploy mechanisms for controlling stomatal development that share common but also deploy distinctive mechanisms to that operating in rosette leaves. The effect of [CO] on stomatal development is retained in cotyledons of the next generation, however, this effect does not occur in pre-germination stomatal lineage cells but only after germination. Finally, these data suggest that [CO] affects regulation of stomatal development specifically through the development of satellite stomata (stomata induced by signals from a neighboring stomate) during spacing divisions and not the basal pathway. To our knowledge, this is the first report identifying developmental steps responsible for altered stomatal patterning to [CO] and its trans-generational inheritance.
气孔通过改变气孔孔径和发育模式来控制水分流失和二氧化碳吸收。气孔模式受包括大气二氧化碳（[CO]）在内的环境因素调节，全球范围内大气二氧化碳正在以前所未有的速度增加。已知成熟叶片会响应[CO]向未成熟叶片传递发育信号，但其发育机制尚不清楚。为了表征从成熟叶片向发育叶片传递信号所导致的气孔模式变化，我们构建了一个双室生长系统，其中拟南芥的莲座叶和茎生叶处于不同的[CO]环境中。发现幼嫩的莲座叶组织会根据当前环境和成熟莲座叶组织所经历的环境来调整气孔指数（SI，气孔数与总细胞数的比例），而茎生叶似乎对[CO]处理不敏感。茎生叶和子叶可能采用了控制气孔发育的机制，这些机制既有共同之处，也有与莲座叶不同的独特机制。[CO]对气孔发育的影响会保留在下一代的子叶中，然而，这种影响在萌发前的气孔谱系细胞中不会出现，而是仅在萌发后出现。最后，这些数据表明，[CO]具体通过在间隔分裂期间卫星气孔（由相邻气孔信号诱导的气孔）的发育来影响气孔发育的调控，而不是通过基础途径。据我们所知，这是第一份确定导致气孔模式对[CO]变化及其跨代遗传负责的发育步骤的报告。
