Stability Properties of Activated Tryptophan Hydroxylase from Rat Midbrain
- 1 September 1982
- journal article
- research article
- Published by Wiley in Journal of Neurochemistry
- Vol. 37 (3) , 601-607
- https://doi.org/10.1111/j.1471-4159.1982.tb12529.x
Abstract
Time courses of the activation-inactivation sequence in rat midbrain tryptophan hydroxylase after preincubation with Ca, ATP + MgCl2 or sulfhydryl reagents and after freezing and thawing suggest that the activated enzyme is more vulnerable to loss of activity. The sequence induced by Ca was prevented by the protease inhibitor leupeptin, and an accelerated decline in activity after activation by ATP + MgCl2 was reduced greatly by increasing levels of tetrahydrobiopterin (BH4) cofactor. The effects of Ca and ATP + MgCl2 were additive, which suggests independent mechanisms. The time courses of enzyme activation and inactivation processes may offer a useful way to study the influence of a range of effectors on tryptophan hydroxylase function.Keywords
This publication has 33 references indexed in Scilit:
- Tyrosine Hydroxylase Activation and Inactivation by Protein Phosphorylation ConditionsJournal of Neurochemistry, 1981
- Activation of tryptophan 5-monooxygenase by calcium-dependent regulator proteinBiochemical and Biophysical Research Communications, 1979
- Conformational influences on brain tryptophan hydroxylase by submicromolar calcium: Opposite effects of equimolar lithiumJournal Of Neural Transmission-Parkinsons Disease and Dementia Section, 1979
- Proteolytic inactivation of a pentafunctional enzyme conjugate: Coordinate protection by the first substrateBiochemical and Biophysical Research Communications, 1978
- Calcium-dependent activation of tryptophan hydroxylase by ATP and magnesiumBiochemical and Biophysical Research Communications, 1978
- Redundant Mechanisms Regulating Brain Tyrosine and Tryptophan HydroxylasesAnnual Review of Pharmacology and Toxicology, 1978
- Leupeptin, a Protease Inhibitor, Decreases Protein Degradation in Normal and Diseased MusclesScience, 1978
- Calcium activation of brain tryptophan hydroxylaseLife Sciences, 1975
- The activation of bovine pineal tryptophan 5‐monooxygenaseFEBS Letters, 1974
- Coenzyme dissociation, a possible determinant of short half-life of inducible enzymes in mammalian liverBiochemical and Biophysical Research Communications, 1973