AMP receptor

The biological relevance of B-A transitions in DNA is of great importance. Protein-DNA association results in an induction of partial deformation in the B-form helix to A-form helix. The cyclic AMP receptor protein is a specific example found to induce a B-A-like transition in its DNA target. Perhaps the most attractive feature of A-DNA is its conformational similarity to duplex RNA. RNA-DNA hybrids, often formed during transcription, are also A-form. 

The stargazer mutant mouse is ataxic and epileptic. It lacks functional AMPA receptors (Fig. 30-1), which apparently are not delivered successfully to the synapses in the cerebellum in which they function.380 386 Mutation of a transmembrane protein stargazin, which may interact with the AMP receptor, causes the symptoms.457 458 NMDA receptors (Fig. 30-20) are involved in synapse formation in the brain. Filopodial extensions on dendrites, triggered by electrical activity, are essential for synapse formation,459 which occurs rapidly.4593 Activation of NMDA receptors is apparently also necessary.379 460 Without this stimulation the excitatory glutamatergic neurons of the developing brain undergo apoptosis. 

Solution Conformation of a Heptadecapeptide Comprising the DNA Binding Helix F of the Cyclic AMP Receptor Protein of Escherichia coli. Combined Use of H Nuclear Magnetic Resonance and Restrained Molecular Dynamics. 

Berg, O. G. and von Hippel, P. H. (1988) Selection of DNA binding sites by regulatory proteins. II. The binding specificity of cyclic AMP receptor protein to recognition sites../. Mol. Biol. 200, 709-723. 

M. P. Jennings and I. R. Beacham. Analysis of the Escherichia coli gene encoding 1-asparaginase II, ansB, and its regulation by cyclic AMP receptor and FNR proteins. J. BacterioL 772 1491 (1990). 

Gerisch, G. D. Malchow. 1976. Cyclic AMP receptors and the control of cell aggregation in Dictyostelium. In Advances in Cyclic Nucleotide Research. 

Klein, P., A. Theibert, D. Fontana P.N. Devreotes. 1985. Identification and cyclic-AMP induced modification of the cyclic AMP receptor in Dictyostelium discoideum. J. Biol. Chem. 260 1757-64. 

Mann, S.K.O. R.A. Firtel. 1987. Cyclic AMP regulation of early gene expression in Dictyostelium discoideum Mediation via the cell surface cyclic AMP receptor. Mol. Cell. Biol. 7 458-69. 

Milne, J. L., and Devreotes, P. N. (1993) The surface cyclic AMP receptors, cARl, cAR2, and cAR3, promote Ca influx in Dictyostelium discoideum by a Ga2-independent mechanism. Mol. Biol. Cell4., 283-292. 

The conformational state of aprotein can have an influence on the exposure of its tryptophan residues to solvent This is illustrated by the cyclic AMP receptor protun (CRP) frcxn Escherichia coli. This protein regulates the expression of over 20 genes in E. coli. CRP consists of two identical polypeptide chains, each containing 209 amino acids. It contains two nonidentical trp residues at positions 13 and 85. 

The discovery of the cyclic AMP receptor protein (CAP) in E. coli is most intriguing because it further illustrates the complexities of gene expression even in a relatively uncomplicated system. In E. coli, cyclic AMP stimulates the elaboration of catabolic enzymes involved in the breakdown of arabinose and maltose [184, 185]. A mutant of E. coli has been found that fails to grow on maltose and arabinose. The mutants lack a protein receptor for the cyclic AMP which is believed to bind probably to DNA, but possibly to RNA, which must be present for the induction of the catabolic enzymes. It has also been shown that in order to secure optimal transcription of the lac operon (see below), both the inducer—for example, isopropyl thio-galactoside—and cyclic AMP must be added. 

In vitro incubation of rat liver microsomes or microsomes and 100,000 xg supernatant with c AMP or c AMP and c AMP receptor protein were unable to modify the A6 desaturation activity of rat liver microsomes to convert linoleic to y-linolenic acid (Table 4)... 

Figure 27.5 DNA molecule ligands bind to the . coli cyclic AMP receptor protein. The fraction of filled sites 6 is shown as a function of the DNA ligand concentration Cj. The dashed line indicates the ligand concentration at half-saturation of the binding sites (see Example 27.1). Source T Heyduk and JC Lee, Proc Natl Acad Sci USA 87, 1744 (1980). 

Derivative 5 g s alsq used in a study of c-AMP receptors in human erythrocyte ghosti. In the dark, it acts as an activator of protein kinase activity and competes with c-AMP for binding. Irradiation causes incorporation of label which is partially blocked by c-AMP. Gel electrophoresis reveals a prominent radioactive band which corresponds in mobility to the endogenous substrate of the membrane protein kinase. 

Crombrugghe, B. de, Chen, B., Anderson, W., Nissley, P., Gottesman, M., Pastan, I., Perlman, R. Lac DNA, RNA polymerase and cyclic AMP receptor protein, cyclic AMP, lac repressor and inducer are the essential elements for controlled lac transcription. Nature (Lond.) New Biol. 231, 139-142 (1971b). 

---