Harold Weiner

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The activity of nitrate reductase (+Mg(2+), NR(act)) in illuminated leaves from spinach, barley and pea was 50-80% of the maximum activity (+EDTA, NR(max)). However, NR from leaves of Ricinus communis L. had a 10-fold lower NR(act), while NR(max) was similar to that in spinach leaves. The low NR(act) of Ricinus was independent of day-time and nitrate(More)
To test a possible role of 14-3-3 proteins in the degradation of nitrate reductase (NR) in leaves, we monitored 14-3-3s bound to NR in leaf extracts. The amount of 14-3-3s that coimmunoprecipitated with serine 543 phospho-NR (p-NR) increased upon a light/dark transition. This was accompanied by a similar increase in the protein turnover rate of NR in(More)
To assess the role of 14-3-3 proteins in the magnesium-dependent inhibition of nitrate reductase (NR) we tested the effect of magnesium on NR binding to 14-3-3s by coimmunoprecipitation and gel filtration. The stability of the 14-3-3 complex of NR was, unlike its activity, unaffected by magnesium. We therefore conclude that binding to 14-3-3s per se does(More)
To monitor site-specific phosphorylation of spinach leaf nitrate reductase (NR) and binding of the enzyme to 14-3-3 proteins, serum antibodies were raised that select for either serine 543 phospho- or dephospho-NR. The dephospho-specific antibodies blocked NR phosphorylation on serine 543. The phospho-specific antibodies prevented NR binding to 14-3-3s, NR(More)
This report describes the development of psychophysical fractionation techniques to assess the effects of drugs. Each of five subjects gave 1/2 estimates of several time and brightness standards, first without drugs, and then under the oral administrations of a placebo and damphetamine sulfate (15 mg) in randomized order. Time fractionations without drugs(More)
Dopamine-derived tetrahydroisoquinolines such as salsolinol and tetrahydropapaveroline have been implicated in alcohol-related problems. Though their infusion into the brain can induce a rat to increase its alcohol consumption, it is not known whether the compounds actually form in vivo. Few investigators have been able to extract the compounds or their(More)
Tetrahydroisoquinolines (TIQs) are not only pharmacologically active, but their intraventricular infusion evokes alcohol drinking in rats. It is not known if salsolinol or tetrahydropapaveroline (THP), the two most commonly studied TIQs, spontaneously form in vivo in brain during chronic or acute consumption of ethanol. A theoretical calculation based on a(More)
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