Three-Dimensional Visualization of Transgenic Tobacco Leaves

We have done a three-dimensional visualization of transgenic tobacco (Nicotiana tabacum) leaves for the study of chloroplast gene expression and regulation. The aim was to visualize tobacco leaves shot with tungsten particles. These tungsten particles were coated with the foreign DNA and shot into the leaf using the biolistic technique of DNA insertion. The visualization can be used to examine the leaves to gauge the efficiency of the shooting process, i.e.,to see what parts of the leaves have been effectively penetrated by the DNA-coated tungsten particles and also to judge the depth of penetration. The image data for the 3D visualization was collected at planes 10 microns apart, using a prototype version of a High Numerical Aperture Reflecting Microscope. The raw image data collected from the microscope was restored using the Row Action Projection (RAP) algorithm and the Partial Minimization and Constrained Iteration (PCMI) algorithm. These restored images were then used for 3D visualization using the Visualization Toolkit.