Dense-core granules

However, an alternative pathway that bypasses clathrin-mediated endocytosis and EEs appears to be available as well. This model of endocytosis known as kiss and run or its variant kiss and stay have attracted increasing interest in recent years [74] (Fig. 9-9B). Kiss and run has been directly demonstrated with dense-core granules in neuroendocrine cells [84, 85], and this model would explain some observations that are not readily accommodated by the classical pathway. The kiss and run model proposes that neurotransmitters are released by a transient fusion pore, rather than by a complete fusion with integration of the synaptic vesicle components into the plasma membrane. Synaptic membrane proteins never lose their association and the vesicle reforms when the pore closes. As a result, the empty vesicle can be refilled and reused without going through clathrin-mediated endocytosis and sorting in the EEs. 

Malosio, M. L., Giordano, T., Laslop, A., and Meldolesi, J. (2004). Dense-core granules A specific hallmark of the neuronal/neurosecretory cell phenotype.. Cell Sci. 117, 743—749. 

Meldolesi, J., Chieregatti, E., and Luisa Malosio, M. (2004). Requirements for the identification of dense-core granules. Trends Cell Biol. 14, 13-19. 

Ramamoorthy, P., and Whim, M. D. (2008). Trafficking and fusion of neuropeptide Y-containing dense-core granules in astrocytes.. Neurosci. 28, 13815-13827. 

In D. dendriticum, a number of types of presumptive aminergic synapses have been described (277) (Fig. 2.10). Evidence that the dense-core granules in this and other species may contain storage granules of a monoamine such as noradrenaline ( = norepinephrine), dopamine or 5-HT is based on microspectrofluorometric analysis, histochemical reactions and biochemical analysis (206, 277, 295-297). 

A.F. Gazdar et al.. Expression of neuroendocrine cell markers L-dopa decarboxylase, chromogranin A, and dense core granules in human tumors of endocrine and nonendocrine origin. Cancer Res. 48 (1988)4078-4082. 

Chen-Chew SB, Leung PY. Species variability in the expression of met- and leu-enkephalin-like immunoreactivity in mammalian Merkel cell dense-core granules a light and electron microscopic immunohistochemical study. Cell Tissue Res. 1992 269 347-351. 

Chromogranin A belongs to a family of acidic secretory proteins associated with dense core granules in a variety of endocrine and neuroendocrine cells (41). A lymphocyte surface marker, Leu7/NHK, cross-reacts with related epitope on the plasma membrane of PNEC and NEB (42). The other NEB cell surface markers include neural adhesion molecule (NCAM) and related epitope MOC-1, originally identified in the small cell lung carcinoma cell line (43,44). 

Zeniou-Meyer M, Zabari N, Ashery U, et al. PhosphoUpase D1 production of phosphatidic acid at the plasma membrane promotes exocytosis of large dense-core granules at a late stage. / Biol Chem. 2007 282(30) 21746-21757. 

Graham, M. E., Burgoyne, R. D. 2000. Comparison of cysteine string protein (Csp) and mutant alpha-SNAP overexpression reveals a role for Csp in late steps of membrane fusion in dense-core granule exocytosis in adrenal chromaffin cells. J. Neurosci. 20 1281-1289. 

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