Functional genomics and biochemistry of shoot apical meristems

几千年来，人类一直在培育和不断改良农作物。尽管有着悠久的共同历史，但我们对这些至关重要的植物是如何生长和发育以产生我们赖以养活、穿衣和庇护我们的器官的了解有限。在科学家设计合理的方法来改良这些作物之前，需要对农学上至关重要的植物器官的新陈代谢进行合理的剖析。所有的植物器官都是由10个干细胞在植物茎和根的顶端分生组织结构中产生的。干细胞解释细胞内的信号，这些信号导致它们分裂并将其子代细胞委托给组织或器官内的特定功能。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。秋季进入休眠状态，春季进入休眠状态，决定了温带地区植物的生活史。当马铃薯在储存中的休眠被打破时，芽开始萌发，并很快导致块茎变得无法商业使用。我们实验室的研究将集中在了解马铃薯芽在休眠解除期间的生化变化，作为控制休眠的第一步。我们将使用新的工具和方法来识别和检测在休眠出现期间充当线索的基因。这些技术包括用于显微解剖和纯化顶端分生组织细胞的激光捕获显微镜技术；用于分离和鉴定这些细胞中的早期出苗特定基因并检测这些基因的表达如何随时间变化的分子生物学技术；以及用于检测这些基因表达的蛋白质的位置和功能的生化技术。我们能够选择正确的组织和正确的时间来检查马铃薯出苗期间的顶端分生组织代谢，这极大地提高了我们找到控制生长的新的、主要的基因的机会。我们实验室研究的最终目标是更好地了解和改进作物，从而直接造福于农业生产者、加工商和消费者。

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.