Transmembrane signaling mechanisms

Ruffolo RR and Hollinger MA (eds.). G-Protein Coupled Transmembrane Signaling Mechanisms. Boca Raton, FL CRC, 1995. 

TRANSMEMBRANE SIGNALING MECHANISMS IN STIMULATION OF PHYTOALEXIN PRODUCTION... 

The novel mechanism of transcriptional control of the ferric citrate transport system via transmembrane signalling is also observed in Pseudomonas putida and probably also occurs in Pseudomonas aeruginosa. Synthesis of the PupB outer... 

The mechanism of action of U ions remains to be fully elucidated. Oiemi-cally, lithium is the lightest of the alkaU metals, which include such biologically important elements as sodium and potassium. Apart from interference with transmembrane cation fluxes (via ion channels and pumps), a lithium effect of major significance appears to be membrane depletion of phosphatidylinositol bisphosphates, the principal lipid substrate used by various receptors in transmembrane signalling (p. 66). 

The signaling mechanisms activated by neurotrophic factors, which include nerve growth factor (NGF), brain derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) are fundamentally different from those discussed for G protein-coupled receptors and Ca " (Russell and Duman 2002). The neurotrophic factors bind to specific receptors, TrkA, TrkB, and TrkC (the name Trk is derived from their identification as troponin/receptor kinases from colon carcinoma) (Fig. 2). The Trk receptors contain an extracellular binding domain, a transmembrane domain, and an intracellular tyrosine kinase domain. Two neurotrophic factor molecules are required for activation of a Trk receptor dimer, resulting in activation of the tyrosine kinase domains and phosphorylation of substrate proteins as well as autophosphorylation of the Trk receptor itself. 

The cell has other transmembrane receptors and signaling pathways that do not fit into the. .classical" receptor types and signal mechanisms described in Chapters 5-11. The following signaling pathways certainly do not complete the list of intercellular and intracellular commimication mechanisms in mammals, and it is to be expected that other classes of signaling pathways will be described in the future. 

Ottensmeyer FP et al Mechanism of transmembrane signalling Insulin binding and the insulin receptor. Biochemistry 2000 39 12103. [PMID ... 

Five basic mechanisms of transmembrane signaling are well understood (Figure 2-5). Each uses a different strategy to circumvent the barrier posed by the lipid bilayer of the plasma membrane. 

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