<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 whose subcellular location is the endoplasmic reticulum, a membrane system continuous with the outer nuclear membrane. It consists of flattened, single-membrane vesicles whose inner compartments, the cisternae, interconnect to form channels throughout the cytoplasm. The rough-surface portion is studded with ribosomes.