Peptide receptor cells

The differentiation effect of lycopene was associated with elevated expression of several differentiation-related proteins, such as cell surface antigen (CD14), oxygen burst oxidase and chemotactic peptide receptors (Amir et al., 1999). Recently, it has also been reported that lycopene was also able to stimulate the differentiation marker alkaline phosphatase activity in... 

Kieffer BL. Recent advances in molecular recognition and signal transduction of active peptides receptors for opioid peptides. Cell Mol Neurobiol 1995 15 615— 635. 

Similarly, five closely related melanocortin receptors that respond to various peptides derived from the POMC precursor have been identified (Fig. 18-7) [24]. As expected, the receptor on adrenal cortical cells responds best to ACTH, which normally stimulates adrenal steroidogenesis, and the receptor on melano cytes responds best to aMSH, which causes skin darkening. However, the pattern of melanocortin receptor expression in the brain is not simply explained by the known patterns of peptide expression in the brain or by the known effects of POMC-derived peptides when applied to various brain regions. With this number of peptide receptors, it is obvious that production of final peptide products must be precisely controlled and that different biosynthetic processing pathways can dramatically affect the biological activity observed (Figs 18-5,18-7). 

Figure 17.1. Neurotransmission (specific case of peptidergic cells). Production of the peptides in the cel I body (1). Packing of the peptides i nto large dense core vesicles for further transport to the axons (2). Release of neuropeptides from the cell soma (3) dendrites (4) and outside of the synapse (5). Release of classic neurotransmitters in the synaptic cleft (6). G-protein-coupled type receptors, which act as peptide receptors. (See color insert.)...

Although many of the investigations aimed at identifying host defense peptide receptors have focused on those localized to the cell surface, it has also been demonstrated that these peptides may utilize intracellular receptors. For example, a 15-residue active fragment of porcine peptide PR-39 has been demonstrated to bind cytosolic adaptor protein pi 30 " resulting in its association with the cytoskeleton and activation of downstream signaling pathways, including Bao et d have also demonstrated that the PR-39 peptide... 

Table 1. Peptide receptors expressed by human primary tumors or tumor cell lines (adapted from references [41-43])...

To determine binding constants between drugs and biological structures (e.g., receptors, cells, peptide fragments), proteins (e.g., enzymes), nucleic acids, and plasmids... 

Olivera, B. M., Conus venom peptides, receptor and ion channel targets, and drug design 50 million years of neuropharmacology, Mol. Biol. Cell, 8, 2101, 1997. 

Pizzi, M., Sarnico, I., Boroni, F., Benarese, M., Steimberg, N., Mazzoleni, G., Dietz, G. P., Bahr, M., Liou, H. C., and Spano, P. F. (2005). NF-acB factor c-Rel mediates neuroprotection elicited by mGlu5 receptor agonists against amyloid /3-peptide toxicity. Cell Death Differ. 12, 761—772. 

Fu W, Jhamandas JH (2003) Beta-amyloid peptide activates non-alpha7 nicotinic acetylcholine receptors in rat basal forebrain neurons. J Neurophysiol 90 3130-3136 Fucile S (2004) Ca2+ permeability of nicotinic acetylcholine receptors. Cell Calcium 35 1-8 Fucile S, Renzi M, Lax P, Eusebi F (2003) Fractional Ca(2+) current through human neuronal alpha nicotinic acetylcholine receptors. Cell Calcium 34 205-209... 

Bitter taste is elicited by structurally diverse compounds, including phenols, ions, amino acids and peptides, alkaloids, acylated sugars, glycosides, nitrogenous compounds, and thiocarbamates. Taste receptor cells are primarily associated with papillae on the tongue. The signal transduction mechanisms by which taste perception occurs are well not understood, but are the focus of intensive research as reviewed recently (6). 

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