PRF/J: Intraspecific Chloroplast-DNA Variation and Phytogeography in the Pacific Northwest

许多植物的地理分布相似， 产于从阿拉斯加东南部到北方加州的地区。 对三个物种的分子遗传学研究显示， 明显的南北细胞质不连续位于南部 威斯康星州冰川最大期 这些数据暗示冰川作用 造成不连续性的可能原因， 植物地理学和遗传学之间联系的可能性 太平洋西北部的植物结构。 如果是这样，其他 具有相似地理分布的植物也应该 表现出相似的遗传变异模式。 本研究 解决了两个问题：（a）类似的地理模式 叶绿体DNA（cpDNA）变异发生在整个光谱 太平洋西北部植物分类群？，(b)是一种变异模式， 细胞质和细胞核标记一致吗 五个人口 分类学上不同的分类群（裸子植物、单子叶植物和双子叶植物 从Dilleniidae，Rosidae和Asteridae）有不同的生活 将使用cpDNA限制性位点检查历史特征 分析、rDNA分析和酶电泳。 从这些 数据，将产生遗传学和遗传模式， 将对变化进行评估。 进一步分析将解决 地理问题，并可能有助于澄清的位置， 疑似冰川避难所的范围。 %%% 我们对种内cpDNA变异程度的了解， 通过这次调查得到加强。 它还将有助于 有助于广泛比较cpDNA的模式和程度 种内变异与核遗传学观察到的变异 标记，提高植物遗传结构的知识， 建立系统学领域之间的重要联系， 群体遗传学

Many plants exhibit a similar geographic distribution, occurring from southeastern Alaska to northern California. Molecular genetic investigations of three species have revealed a pronounced north-south cytoplasmic discontinuity located south of the Wisconsin glacial maximum. These data implicate glaciation as a possible causal factor in creating the discontinuity and raises the possibility of a link between phytogeography and the genetic architecture of plants in the Pacific Northwest. If so, then other plants displaying similar geographic distributions should also exhibit similar patterns of genetic variation. This study addresses two questions: (a) do similar geographic patterns of chloroplast DNA (cpDNA) variation occur throughout a spectrum of Pacific Northwest plant taxa?, (b) are patterns of variation in cytoplasmic and nuclear markers congruent? Populations of five taxonomically diverse taxa (a gymnosperm, a monocot, and dicots from Dilleniidae, Rosidae, and Asteridae) having different life history features will be examined using cpDNA restriction site analysis, rDNA analysis, and enzyme electrophoresis. From these data, phylogenies will be generated and patterns of genetic variation will be assessed. Further analysis will address biogeographical questions and may help clarify the location and extent of suspected glacial refugia. %%% Our knowledge of the extent of intraspecific cpDNA variation will be enhanced through this investigation. It will also serve to facilitate a broad comparison of patterns and extent of cpDNA variation within species to that observed for nuclear genetic markers, improve knowledge of plant genetic architecture, and establish an important link between the areas of systematics and population genetics.