Switch 1 mutants

Magariyama, Y., Yamaguchi, S. and Aizawa, S.-I. (1990). Genetic and behavioral analysis of flagellar switch mutants of Salmonella typhimurium. J. Bacteriol. 172, 4359-4369. 

Silverman, M. and Simon, M. (1980). Phase variation genetic analysis of switching mutants. Cell 19, 845-854. 

Harbury, P.H., et al. A switch between two-, three-, and four-stranded coiled coils in GCN4 leucine zipper mutants. Science 262 1401-1407, 1993. 

Baron U, Schappinger D, Helbl Vet al (1999) Generation of conditional mutants in higher eukaryotes by switching between the expression of two genes. Proc Natl Acad Sci USA 96 1013-1018... 

Studies in knockout mice indicate that the p2 nAChRs are necessary for nicotine self-administration, DA-dependent locomotor activation, and nicotine-associated enhancement of NAc DA release.40-51 53 Combined with studies showing that antagonism of the high-affinity nAChRs block self-administration,44-54 it would appear that p2 nAChRs are particularly critical for nicotine reinforcement. Unlike wild-type mice that self-administer both cocaine and nicotine, p2 nAChR-null mutant mice learn to self-administer cocaine normally, but stop bar pressing as though receiving saline when cocaine is switched to nicotine.40 Self-administration of VTA nicotine and associated DA release is rescued, however, in p2 nAChR knockout mice with lentiviral-mediated expression of P2 subunit DNA in the VTA.55 Whereas several configurations of the p2 nAChRs exist at the... 

L-Pro <3, 4, 5> (<3> enzyme from strain PAOl 5mM, 50% inhibition, complete inhibition at 30 mM, noncompetitive. Strain PAO 879, a proline-auxo-troph mutant lacks a proline-inhibitable y-glutamyl kinase [5] <4> 150 = 0.08 mM, at room temperature. At low temperatures the inhibition switches over into allosteric activation and the biosynthesis of proline is started [7] <4> feedback-inhibition [8]) [5, 7, 8, 10]... 

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