<p>An evidence describes the source of an annotation, e.g. an experiment that has been published in the scientific literature, an orthologous protein, a record from another database, etc.</p>
Protein which is membrane-bound or membrane-associated. A membrane is the layer which forms the boundary of cells and intracellular organelles. It is composed of two oriented lipid layers in which proteins are embedded and acts as a selective permeability barrier.