Dissertation Research: Molecular Phylogenetics of Phlebia (Basidiomycotina) and Related Genera

真菌的分类研究是困难的，因为这些生物的简单形态和可塑性。DNA分析是解决真菌分类学问题的一种很有希望的方法。真菌中有两种DNA:(1)发生在线粒体中的DNA (mtDNA)，并编码线粒体（能量）功能所需的基因；(2)细胞核中编码所有其他基因的DNA。由于mtDNA易于提取和表征，它在真菌分类研究中受到青睐。限制性内切位点的定位和保守基因的测序是研究真菌mtDNA的最好方法。研究生Karen Nakasone在指导老师Ken Sytsma博士的指导下，将获得这两种数据。数据分析将从两个基本方面进行：(1)计算样本之间的总体遗传相似性；(2)确定类群之间的系统发育关系。Phlebia属由小而不显眼但普遍存在的真菌组成，它们会腐烂木材。一些树种在木材生物力学制浆方面显示出很大的潜力。本研究的目的是：(1)根据形态学、实验室培养和DNA特征对北美30-35种白蛉进行划分和定义，并评估传统形态学特征在其分类中的可靠性；(2)确定麻属内各物种的系统发育关系以及麻属与其他属的系统发育关系；(3)研究菲利比亚mtDNA的遗传，并将这些发现与其他真菌联系起来。这项研究将有助于建立这些真菌的可靠分类，一个反映进化关系的分类。

The taxonomic study of fungi is difficult because of the simple morphology and plasticity of these organisms. One method that shows great promise in resolving questions in fungal taxonomy is DNA analysis. In fungi there are two kinds of DNA: (1) DNA that occurs in the mitochondria (mtDNA) and encodes genes necessary for mitochondrial (energy) functions; and (2) DNA in the nucleus encoding all other genes. Because mtDNA is easy to extract and characterize, it has been favored in taxonomic studies of fungi. Mapping of restriction sites and sequencing of conserved genes are the best approaches to study mtDNA in fungi. Graduate student Karen Nakasone, under the direction of faculty adviser Dr. Ken Sytsma, will obtain both kinds of data. The data will be analyzed in two basic ways: (1) to calculate overall genetic similarity between samples and (2) to determine phylogenetic relationships between taxa. The genus Phlebia consists of small and inconspicuous but ubiquitous fungi that decay wood. Some species show great potential in the biomechanical pulping of wood. The objectives of this study are: (1) to delimit and define the 30-35 species of Phlebia that occur in North America based on morphology, laboratory cultures, and DNA characteristics and to assess the reliability of traditional morphological characters in their taxonomy; (2) to determine the phylogenetic relationships of species within Phlebia and of Phlebia to other genera in the family; and (3) to study the inheritance of mtDNA in Phlebia and relate these findings to other fungi. The study will contribute to establishing a reliable taxonomy of these fungi, one that reflects evolutionary relationships.