Eukaryotic cells being organised as a tissue, an organ or an organ system are in contact with either other eukaryotic cells or the extracellular matrix. Cell junctions are basically categorised as tight, anchoring and communicating junctions.
Initiation: Extracellular and Membrane Events, Transmission: Effectors and Cytosolic Events, Nuclear Responses: Gene Expression and Translation, Events in Intracellular Compartments, Cell-Cell and Cell-Matrix Interactions