Abstract
During cell signalling, information that is encoded by ligands travels from one place, the source, to another, the target, where signals are transduced by receptors. Evidence has emerged recently that uncovers a role for the endocytic pathway in the secretion of ligands at the source, their dispersion through developing target tissues and the transduction of the signals from endocytic compartments. As a result, endosomes have become the focus of attention in cell-cell communication studies.
