An acidic protein found in the NEUROENDOCRINE SYSTEM that functions as a molecular chaperone for PROPROTEIN CONVERTASE 2.
Tumors whose cells possess secretory granules and originate from the neuroectoderm, i.e., the cells of the ectoblast or epiblast that program the neuroendocrine system. Common properties across most neuroendocrine tumors include ectopic hormone production (often via APUD CELLS), the presence of tumor-associated antigens, and isozyme composition.
A group of carcinomas which share a characteristic morphology, often being composed of clusters and trabecular sheets of round "blue cells", granular chromatin, and an attenuated rim of poorly demarcated cytoplasm. Neuroendocrine tumors include carcinoids, small ("oat") cell carcinomas, medullary carcinoma of the thyroid, Merkel cell tumor, cutaneous neuroendocrine carcinoma, pancreatic islet cell tumors, and pheochromocytoma. Neurosecretory granules are found within the tumor cells. (Segen, Dictionary of Modern Medicine, 1992)
A system of NEURONS that has the specialized function to produce and secrete HORMONES, and that constitutes, in whole or in part, an ENDOCRINE SYSTEM or organ.
Specialized NEURONS that produce hormones, such as NEUROPEPTIDES or BIOGENIC AMINES. They generally are in the NERVOUS SYSTEM, such as HYPOTHALAMUS, but can be found in other organs or systems. These neurons contain dense neurosecretory granules and PROPROTEIN CONVERTASES allowing the rapidly release of NEUROHORMONES into the blood circulation upon stimulation.
Proteins secreted by the prostate gland. The major secretory proteins from the human prostate gland include PROSTATE-SPECIFIC ANTIGEN, prostate-specific acid phosphatase, prostate-specific membrane antigen, and prostate-specific protein-94.
A group of acidic proteins that are major components of SECRETORY GRANULES in the endocrine and neuroendocrine cells. They play important roles in the aggregation, packaging, sorting, and processing of secretory protein prior to secretion. They are cleaved to release biologically active peptides. There are various types of granins, usually classified by their sources.
A type of chromogranin which was first isolated from CHROMAFFIN CELLS of the ADRENAL MEDULLA but is also found in other tissues and in many species including human, bovine, rat, mouse, and others. It is an acidic protein with 431 to 445 amino acid residues. It contains fragments that inhibit vasoconstriction or release of hormones and neurotransmitter, while other fragments exert antimicrobial actions.
A steroid-inducible protein that was originally identified in uterine fluid. It is a secreted homodimeric protein with identical 70-amino acid subunits that are joined in an antiparallel orientation by two disulfide bridges. A variety of activities are associated with uteroglobin including the sequestering of hydrophobic ligands and the inhibition of SECRETORY PHOSPHOLIPASE A2.
Proteins secreted by the epididymal epithelium. These proteins are both tissue- and species-specific. They are important molecular agents in the process of sperm maturation.
Proteins found in SEMEN. Major seminal plasma proteins are secretory proteins from the male sex accessory glands, such as the SEMINAL VESICLES and the PROSTATE. They include the seminal vesicle-specific antigen, an ejaculate clotting protein; and the PROSTATE-SPECIFIC ANTIGEN, a protease and an esterase.
Proteins and peptides found in SALIVA and the SALIVARY GLANDS. Some salivary proteins such as ALPHA-AMYLASES are enzymes, but their composition varies in different individuals.
A usually small, slow-growing neoplasm composed of islands of rounded, oxyphilic, or spindle-shaped cells of medium size, with moderately small vesicular nuclei, and covered by intact mucosa with a yellow cut surface. The tumor can occur anywhere in the gastrointestinal tract (and in the lungs and other sites); approximately 90% arise in the appendix. It is now established that these tumors are of neuroendocrine origin and derive from a primitive stem cell. (From Stedman, 25th ed & Holland et al., Cancer Medicine, 3d ed, p1182)
A system of cisternae in the CYTOPLASM of many cells. In places the endoplasmic reticulum is continuous with the plasma membrane (CELL MEMBRANE) or outer membrane of the nuclear envelope. If the outer surfaces of the endoplasmic reticulum membranes are coated with ribosomes, the endoplasmic reticulum is said to be rough-surfaced (ENDOPLASMIC RETICULUM, ROUGH); otherwise it is said to be smooth-surfaced (ENDOPLASMIC RETICULUM, SMOOTH). (King & Stansfield, A Dictionary of Genetics, 4th ed)
A type of chromogranin which was initially characterized in a rat PHEOCHROMOCYTOMA CELL LINE. It is found in many species including human, rat, mouse, and others. It is an acidic protein with 626 to 657 amino acid residues. In some species, it inhibits secretion of PARATHYROID HORMONE or INSULIN and exerts bacteriolytic effects in others.
Chymotrypsinogen is a zymogen, specifically an inactive precursor form of the enzyme chymotrypsin, which is produced in the pancreas and activated in the small intestine to help digest proteins by cleaving specific peptide bonds.
Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.
A stack of flattened vesicles that functions in posttranslational processing and sorting of proteins, receiving them from the rough ENDOPLASMIC RETICULUM and directing them to secretory vesicles, LYSOSOMES, or the CELL MEMBRANE. The movement of proteins takes place by transfer vesicles that bud off from the rough endoplasmic reticulum or Golgi apparatus and fuse with the Golgi, lysosomes or cell membrane. (From Glick, Glossary of Biochemistry and Molecular Biology, 1990)
A saclike, glandular diverticulum on each ductus deferens in male vertebrates. It is united with the excretory duct and serves for temporary storage of semen. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)