Functional genomics and biochemistry of shoot apical meristems

几千年来，人类一直在种植和不断改良农作物。尽管有着悠久的共同历史，但我们对这些至关重要的植物如何生长发育，产生我们赖以生存、穿衣和居住的器官，却知之甚少。在科学家能够设计合理的方法来改良这些作物之前，需要对农艺学上关键的植物器官的代谢进行逻辑解剖。所有的植物器官都是由植物茎和根中被称为顶端分生组织的结构中的10个干细胞产生的。干细胞解释导致它们分裂的细胞内信号，并使它们的子细胞在组织或器官中发挥特定的功能。这些信号的特定组合可以改变植物的生长模式，例如通过休眠过程控制营养生长的速度，特别是通过停止和重新启动干细胞的分裂和分化。秋天进入休眠，春天从休眠中出来，这决定了温带植物的生命周期。当马铃薯在储藏中的休眠状态被打破时，芽开始发芽，很快导致块茎在商业上无法使用。我们实验室的研究将集中在了解马铃薯芽在休眠期间的生物化学变化，作为控制它的第一步。我们将使用新的工具和方法来识别和检查在休眠出现期间作为线索的基因。这些技术包括用于茎尖分生组织干细胞显微解剖和纯化的激光捕获显微镜；分子生物学技术分离和鉴定这些细胞中的早期出现特异性基因，并检查这些基因的表达如何随时间变化；以及检查这些基因表达的蛋白质的位置和功能的生化技术。我们选择合适的组织和合适的时间来检查马铃薯茎尖分生组织代谢的能力，显着提高了我们发现控制生长的新主要基因的机会。我们实验室研究的最终目标是更好地了解和改良作物，从而直接造福农业生产者、加工者和消费者。

Crop plants have been cultivated and continuously improved by humans for thousands of years. Despite this long shared history, we have only a limited understanding of how these crucially important plants grow and develop to produce the organs we rely on to feed, clothe and shelter us. The logical dissection of the metabolism of agronomically critical plant organs is required before scientists can design rational methods to improve these crops. All plant organs arise from as few as ten stem cells in structures in the plant shoot and root called apical meristems. The stem cells interpret intracellular signals that cause them to divide and commit their daughter cells to specific functions within tissues or organs. Specific combinations of these signals can shift the growth pattern of the plant, for example by controlling the rate of vegetative growth through the process of dormancy, specifically by stopping and restarting division and differentiation of the stem cells. Entering dormancy in the autumn and emerging from it in the spring define the life cycle of temperate region plants. When dormancy is broken in potatoes in storage, the buds begin to sprout and quickly result in the tubers becoming commercially unusable. Research in our lab will center around understanding how the biochemistry of potato buds changes during dormancy break as a first step towards controlling it. We will use new tools and methods to identify and examine the genes that serve as cues during dormancy emergence. These techniques include laser capture microscopy for microdissection and purification of shoot apical meristem stem cells; molecular biology techniques to isolate and identify early emergence-specific genes in these cells and examine how expression of these genes changes over time; and biochemical techniques for examination of the location and function of proteins expressed by these genes. Our ability to choose the right tissue and the right time to examine potato shoot apical meristem metabolism during emergence significantly improves our chances of finding novel, cardinal genes controlling growth. The ultimate goal of research in our lab is to better understand and improve crops and thus directly benefit agricultural producers, processors and consumers.