Dissertation Research: A Molecular Investigation of Higher Level Phylogeny of the Conifers

博士生琳达劳贝森在 监督利奥希基博士在耶鲁大学，将承担 研究了7个科的进化史， 针叶树（松树），基于两种分子数据， 叶绿体DNA（cpDNA）结构重排和序列 来自核18S rDNA（核糖体）基因的数据。以来的时间 这7个家族成为独立的进化谱系， 据估计有3亿年之久;选择的分子 性格在进化上是保守的， 在这个时间深度的信息。拟议的研究时间表 涵盖两年;虽然，耶鲁大学的博士生，Raubeson 第一年将和罗伯特·詹森一起做cpDNA研究 在康涅狄格大学， 在路易斯安那州立大学与伊丽莎白·齐默进行了一年的18S rDNA基因测序。 这位学生已经从23个物种中分离出了总DNA 包括所有7个家庭的代表， 限制酶切和作图。齐默测序了 针叶树的18s rDNA基因部分。两种数据类型 似乎在适当的时间深度提供了信息。的 完成的研究将澄清我们对 这个经济上重要的组合的进化史 树木的。

The doctoral student, Linda Raubeson, working under the supervision of Dr. Leo Hickey at Yale University, will undertake a study of the evolutionary history of the 7 families of conifers (pines), based on two kinds of molecular data, chloroplast DNA (cpDNA) structural rearrangements, and sequence data from the nuclear 18s rDNA (ribosomal) gene. The time since the 7 families became separate evolutionary lineages is estimated to be 300 million years; the chosen molecular characters are evolutionarily conservative and should be informative at that time depth. The proposed research timetable covers two years; although, a doctoral student at Yale, Raubeson will spend the first year doing the cpDNA work with Robert Jansen at the University of Connecticut and six months of the second year sequencing the 18s rDNA genes with Elizabeth Zimmer at LSU. The student has already isolated total DNA from 23 species including representatives of all 7 families and has done limited restriction enzyme digests and mapping. Zimmer has sequenced portions of the 18s rDNA gene for conifers. Both data types appear to be informative at the appropriate time depth. The completed research will clarify our understanding of the evolutionary history of this economically important assemblage of trees.