||The Transforming Growth Factor-ß (TGF-ß) is the founding member of a multifunctional family of signal proteins that regulate many aspects of cell physiology, including cell growth, differentiation, motility and death and play important roles in many developmental and pathological processes. TGF-ß signals through binding to two types receptors. These receptors activate a family of intracellular mediators called Smad. The Smad complexes that move in to the nucleus associate with gene regulatory proteins, bind to specific sites of DNA and activate a set of target genes. Understanding the nuclear localization of the Smad complexes has direct implications to their functions. Studying these complexes can be done by fluorescent markers that bind specifically to the objects of interest using proximity ligation assays (PLA).
In this Monday seminar I will talk about fluorescent images with this type of staining made both at the Wide Field microscope and the Laser Scanning Confocal Microscope. The tasks at hand are the single cell delineation in 3D and the segmentation and localization of the point-source signals (the PLA product) in relation to the cell nucleus. The level of accuracy needed in single cell delineation is high in order to have an accurate measure of the spatial distribution of the point-source signals. The findings are expected to help biologist further discuss the biological implications of the localization of Smad complexes.