U.S.-Austria Cooperative Research: A Model for Plastid Evolution--Cyanophora Cyanelle DNA (Molecular Biology)

该奖项将支持亚利桑那大学生物化学系汉斯·J·博纳特教授和奥地利维也纳大学普通生物化学研究所沃尔夫冈·洛费尔哈特博士之间为期两年的合作研究项目。科学家和他们的研究小组成员将研究反常蓝藻蓝藻DNA的基因组和基因结构。他们将试图确定(1)蓝藻DNA上的几个基因/操纵子的结构，这些基因/操纵子在蓝藻和高等植物叶绿体DNA中以不同的方式组织；(2)蓝藻依赖于从周围细胞质输入蛋白质的程度，以及这种运输是如何实现的，无论是不同于或相同于高等植物的运输。这项工作的长期目标是通过监测研究得很好的高等植物叶绿体特征和蓝藻基因组之间的差异，了解哪些进化选择可以允许光合作用活跃的细胞器整合到真核细胞的新陈代谢中。蓝藻中的蓝藻是一个叶绿体的例子，它是植物细胞的一种被膜包裹的成分。叶片中的叶绿体是另一个更广为人知的例子。在这项研究中，合作的科学家将进行生化和分子生物学研究，旨在证明蓝藻基因与高等植物叶绿体中的基因和蓝藻基因的关联程度。这项工作包括对几个氰化物染色体区域进行测序，这些区域是根据它们在进行这些比较时的预期价值而选择的。通过这种方式，可能会收集到特定基因进化的证据，从简单的细菌到蓝藻，再到更高级的植物，如树木。博纳特教授在分子生物学和植物遗传学方面经验丰富。Loeffelhardt教授是一位生物化学家，在处理这些实验中要研究的蛋白质方面有经验。他们的专业知识将被结合在一项研究中，预计这项研究将揭示位于生物不同细胞隔间的基因的进化，而生物的进化史还没有被很好地理解。

This award will support a two-year cooperative research project between Professor Hans J. Bohnert, Department of Biochemistry, University of Arizona, and Dr. Wolfgang Loeffelhardt, Institute for General Biochemistry, University of Vienna, Austria. The scientists and members of their research groups will study the genome and gene structure of cyanelle DNA from Cyanophora paradoxa. They will attempt to determine (1) the structure of several genes/operons on cyanelle DNA which are differently organized in cyanelle and higher plant chloroplast DNA and (2) the extent to which the cyanelle is dependent on import of proteins from the surrounding cytoplasm and how this transport is achieved, either differently from or identically to the transport in higher plants. The long-term goal of the work is to understand, by monitoring differences between the well-studied higher plant chloroplast characteristics and the cyanelle genome, which evolutionary options were available to permit a photosynthetically active organelle to be integrated into the metabolism of a eukaryotic cell. The cyanelle in Cyanophora paradoxa is an example of a plastid, a membrane-enclosed component of a plant cell. Chloroplasts in leaves are another, better-known example. In this study, the cooperating scientists will carry out biochemical and molecular biological studies aimed at demonstrating the degree of relatedness of cyanelle genes to those in higher plant chloroplasts and to cyanobacterial genes. The work involves sequencing several cyanelle chromosome regions selected for their anticipated value in making these comparisons. In this way it may be possible to gather evidence for the evolution of specific genes from simple bacteria through Cyanophora paradoxa to still higher plants, such as trees. Professor Bohnert is experienced in molecular biology and plant genetics. Professor Loeffelhardt is a biochemist with experience in working with the proteins to be studied in these experiments. Their expertise will be combined in a study which is expected to shed light on the evolution of genes that are located in different cellular compartments in an organism whose evolutionary history is not well understood.