Physikalische Kartierung und Genexpressionsanalysen im Genom von Neurospora crassa

Abstract

The filamentous fungus Neurospora crassa has been used as a model organism in basic science for more than 50 years. In germany, a neurospora genome project started in 1998 that aims at the sequencing of the chromosomes II and V.The physical maps described in the first part of this work formed the basis of the sequencing project. For mapping, a cosmid library with a 17-fold genomic coverage and a BAC library with a 15-fold coverage were used, from which chromosome specific sublibraries were selected. Physical mapping was done by hybridising labelled DNA of single clones to the libraries. Ordering of the clones according to their hybridisation pattern was performed with an established software package. The resulting map of chromosome II contains 13 regions, the map of chromosome V 21 regions of overlapping clones (contigs).In the second part of the work some gene expression profiling experiments were performed using selfmade cDNA microarrays of N. crassa. By hybridising complex RNA probes transcriptional profiles were generated for three different growth conditions of mycelium of N. crassa. In each experiment, two mRNA populations were labelled by reverse transkription with two different fluorescent dyes and cohybridised to a single chip. After detection and quantification of the signal intensities, factors for induction or repression of the genes were calculated and visualised in a correspondence analysis.