DARPP-32 (dopamine and cAMP-regulated phosphoprotein, Mr 32,000) is a membrane protein in the bovine parathyroid

• Published in: FEBS letters Vol. 364; no. 1; pp. 67 - 74
• Main Authors: Matovcik, Lisa M., Hemmings, Hugh C., Kinder, Barbara K.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-05-1995
• Subjects: DARPP-32; Parathyroid; Protein phosphatase-1; PTH secretion; DARPP-32; PTH secretion; Parathyroid; Protein phosphatase-1
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(95)00359-H

A distinct form of DARPP-32, a protein phosphatase-1 inhibitor, has been identified in bovine calf parathyroid glands. Immunoblot analysis of parathyroid tissue revealed a 32 kDa protein present predominantly in a particulate fraction; it remained particulate after treatment with 1.0 M NaCl or 0.1 M Na
2CO
3. Metabolic labeling of parathyroid cells with mevalonolactone demonstrated that DARPP-32 is isoprenylated. Immunocytochemical localization studies demonstrated that DARPP-32 is present in vesicles throughout the cytoplasm of parathyroid cells, and that protein phosphatase-1γ is concentrated in the region of the plasma membrane. Thus, in contrast to the predominately soluble form of DARPP-32 that has been characterized in selected areas of the central nervous system, the parathyroid form is tightly associated with intracellular membranes.