ABSTRACT Exosomes are small extracellular vesicles secreted by cells. Exosomes carry bioactive molecules such as signaling proteins and mRNAs, and potently affect the pathophysiology of their recipient cells. The project funded by my R35 grant “Molecular Basis and Regulatory Mechanisms of Exosome Secretion” (R35 GM141832) aims to understanding the molecular mechanisms that control the biogenesis and secretion of exosomes, and the regulation of exosome biogenesis by oncogenic signaling. A combination of molecular biology and biochemistry approaches were proposed to understand exosome secretion at the molecular level. Molecular cloning and protein analysis will be performed through the project. In this proposal, supplement fund is requested for the purchase of a Bio-Rad documentation system to replace our broken and outdated unit. This is a basic piece of equipment for the capture and storage of the images of nucleotide acid and protein gels, and is indispensable for the accomplishment of the goals proposed in the parent R35 grant.