A 3-dimensional structural analysis of diploid chromosomes

• Main Author: Gunawardena, Shermali Dione Shiranthini Harina
• Other Authors: Rykowski, Mary C.
• Language: en_US
• Published: The University of Arizona. 1994
• Online Access: http://hdl.handle.net/10150/626984; http://arizona.openrepository.com/arizona/handle/10150/626984

In this study, we are looking at the 3-dimensional chromosome structure of interphase diploid nuclei of Drosophila melanogaster. The goal is to determine the higher order structure of interphase chromosomes in these nuclei. Higher order structures include those structures larger than the 30nm fiber. Over the years, several general models for higher order chromosome structures have been presented. We look at three popular models for the organization of chromatin during embryogenesis, as each of these models make predictions that can be tested using high resolution in situ hybridization and image processing techniques. For this study we are using the Notch gene for in situ hybridization to embryos in cycles 10-14.Our preliminary results are inconsistent with the radial loop model. It appears that the chromatin might be arranged in folds of 30 and 10nm fibers. We also observe a difference in chromatin structure as the embryo gets older. As the Notch gene is being transcribed during cycle 14 we observe a puffing event. In this study we hope to expand on these observations and present further areas that need to be explored in order to conclusively distinguish these phenomena during early embryogenesis.