Granule precursor cells

Nicot, A., Lelievre, V., Tam, J., Waschek, J. A., and DiCicco-Bloom, E. (2002). Pituitary adenylate cyclase-activating polypeptide and sonic hedgehog interact to control cerebellar granule precursor cell proliferation. J. Neurosci. 22, 9244-9254. 

Wallace VA (1999) Purkiiije-ce 11-derived sonic hedgehog regulates granule neui on precursor cell proliferation in die developing mouse cerebellum. Cuit Biol 9 445 448. 

Nover, L., Scharf, K. D., and Neumann, D. (1989). Cytoplasmic heat shock granules are formed from precursor particles and are associated with a specific set of mRNAs. Mol. Cell Biol. 9, 1298-1308. 

P2Y receptors are activated by adenine and uridine nucleotides. Most of the known P2Y receptors have been detected in the nervous system [21]. The majority of P2Y receptors inhibit neuronal N-type Ca2+ channels and M-type K+ channels. P2Y1 receptors are found exclusively on platelets, on their precursor megakaryocyte cells and on certain other cultured hematopoietic cells, such as K562 leukemia cells. They can be distinguished from other P2 receptors in that ADP is the most potent natural agonist and ATP is a competitive antagonist. ADP acts via a G protein to inhibit cyclic AMP accumulation, mobilize intracellular Ca2+ and stimulate granule secretion. ADP... 

These cells are relatively undifferentiated and have a large nucleus, distinguishable nucleolus but few, if any, cytoplasmic granules. Myeloblasts arise from a precursor pool of stem cells, and both the rough endoplasmic reticulum and the Golgi apparatus stain for peroxidase, indicating that this enzyme is beginning to be synthesised. This cell type is capable of proliferation. 

Gould, E., Tanapat, P., McEwen, B.S., Flugge, G., Fuchs, E. (1998). Proliferation of granule cell precursors in the dentate gyrus of adult monkeys is diminished by stress. Proc Natl Acad Sci, USA 95, 3168-71. 

Site of synthesis and secretion Enzyme that degrades insulin and its source Half-life of insulin Insulin is a polypeptide hormone produced by thep cells of the islets of Langerhans of the pancreas. Its synthesis involves two inactive precursors, preproinsulin and proinsulin, which are subsequently cleaved to form the active hormone. Insulin is stored in the cytosol in granules that are released by exocytosis Insulin is degraded by the enzyme insulinase produced primarily by the liver. Insulin has a plasma half-life of approximately six minutes. 

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