Since X. tropicalis has 10 haploid chromosomes each with different morphology, we hope to be able to develop cytogenetic techniques to better understand genomic structure and as a tool to map mutant loci. Our approach will have two main goals:
We hope to develop methods in which to visualize chromosome banding patterns. Chromosome banding patterns will allow us to look for gross changes in chromosome morphology as a result of mutagenesis especially with gamma rays. In order to visualize banding patterns, we will need to develop a system for primary cell culture of X. tropicalis cells.
Oocytes have chromosomes with the DNA looped out from chromomeres to allow a high rate of access to the transcriptional machinery. These lampbrush chromosomes allow for very high resolution cytology. Also BAC's can be directly hybridized to lampbrush chromosomes to assess for deletions in potential heterozygote individuals. We hope to develop protocols to efficiently produce these lampbrush chromosome spreads. This technique should allow us to identify a library of animals that have different deletions that can be mapped using BAC hybridization of lampbrush chromosomes.
Currently we are still in the very preliminary stages of this aim. As we develop protocols that are successful in cytological analysis, we will make them available.