Interaction with calmodulin

Sorensen, S. D., Macek, T. A., Cai, Z Saugstad, J. A., and Conn, P. J. (2002) Dissociation of protein kinase-mediated regulation of metabotropic glutamate receptor 7 (mGluR7) interactions with calmodulin and regulation of mGluR7 function. Mol. Pharmacol. 61,1303-1312. 

Hg2 + has been shown to interact with calmodulin and Hg2+ is capable of... 

Dark-shaded residues interact with calmodulin s C-terminal domain. Light-shaded residues interact with calmodulin s N-terminal domain. For CaMKK peptides, the reverse is true. 

Calcium ion interactions with calmodulin, THERMODYNAMIC CYCLES Calcium oxalate,... 

Fig. 7. (A) Aligned, partial sequences of a number of calmodulin-binding peptides. The boxes indicate residues that are generally occupied by apolar residues. Reported dissociation constants for interaction with calmodulin are given on the right. LK2, A mode peptide VIP, vasoactive intestinal peptide GIP, gastric inhibitory peptide. (B) The mean hydropho-bicities for the residues at a given position were plotted versus their position in the aligned sequence. The horizontal bar indicates the period of an a helix. From Cox et al. (1985).

In contrast to the other members of the PDE family, PDE1 is unique in its ability to interact with calmodulin. As would be expected therefore, this interaction can also be the target of potential inhibitors. This appears to be so for some natural-product inhibitors of PDE1 isolated from ginseng root. The ginsenosides Rb, Rc, and Re are moderately active (5-15 pM) steroidal inhibitors of CaM PDE isolated... 

Protein Protein Interactions with Calmodulin and Gal3 and Translocates It from the PM, Converting It to a Death-Inducing Protein... 

Endocytosis may not be required for the entry of an invasive adenylate cyclase from Bordello pertussis (Hanski and Ferfel, 1985 Donovan and Storm, 1990). This is a single chain protein (mol. wt. approx. 200 kDa) which resembles the edema factor from anthrax toxin in that it must interact with calmodulin to become active. In contrast to anthrax toxin, it consists of only one polypeptide which is, however, easily cleaved by proteases and thereby activated. An enzymatically active 45 kDa fragment is not active on whole cells, but it could in conjunction with the rest of the molecule enter the cytosol. The facts that this toxin acts much more rapidly than anthrax toxin, and that it is active even at 4 °C and on erythrocytes that have little, if any, endocytosis, suggest that the toxin is able to penetrate directly through the cell surface membrane. 

The influence of Cd on physiological Ca " signaling has been reviewed elsewhere [460] and the role of Ca in Cd -induced ceU death is detailed in Section 5.5.4.2. Many groups have reported the release of Ca " following Cd " treatment but these data have to be taken with care as Cd Nbinding fluorescent dyes, or inhibitors, such as Fura-2 or BAPTA-AM, were employed. Cd " can increase cytosolic Ca by inactivating the SERCA pump and calmodulin-dependent Ca " ATPases. In addition, Cd is well known to interact with calmodulin to activate CaMKII [481] as well as affect calreticulin-mediated signaling [482]. 

Gachhui, R., Abu-Soud, HAl., Ghosha, D.K., Presta, A., Blazing, M.A., Mayer, B., George, S.E., and Stuehr, D.J. (1998). Neuronal nitric-oxide synthase interaction with calmodulin-troponin C chimeras. J. Biol. Chem. 275(10), 5451-5454. 

Melittins are peptides of 26 amino acids found in Apis venoms (119, 120). Melittin comprises about 40% to 50% of the dry weight of Apis mellifera venom. At moderate and high concentrations, it exists primarily in the form of tetramers (120, 121), which can be immunogenic and allergenic (123). Tetrameric melittin is a potent lytic agent for cells and can also function as an ion channel (124, 125, 126). Melittin has profound effects on intracellular calcium and interacts with calmodulin (127, 128, 129). It is an amphiphilic and amphipathic molecule that has been found to be very useful in studies of cell lysis, membrane function, calcium regulation and as a model for proteins and peptides. Natural and synthetic melittin have been used in over a 1000 published studies in many areas of science. 

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