Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.26 (invertase)
 4,927 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Saccharomyces cerevisiae -136ts (Hutchison, H.T., Hartwell, L.H. and McLaughlin, C.S. (1969) J. Bacteriol. 99, 807-814) incubated in the presence of maltose at 23 degrees C (permissive temperature) synthesized the RNA messengers which codify derepressed invertase (an external mannoprotein) and induced alpha-glucosidase (a non-glycosylated internal enzyme). The enzymes were not synthesized if the mutant was transferred to the maltose-containing medium at the moment of incubation at 37 degrees C indicating that the cells had no pools of the specific RNA messengers and that transcription of the DNA was a prerequisite to enzyme synthesis. Cycloheximide inhibited syntheses of the enzymes both at 37 and at 23 degrees C suggesting that the enzymic activities were the result of "de novo" synthesis of the proteins and did not result from the activation of proenzymes. In derepressed cells the number of invertase mRNA molecules is probably larger than that actually being translated. The half-life of the derepressed invertase mRNA was calculated from the moment that the molecules of RNA messenger were limiting the enzyme synthesis and a value of 30-35 min was estimated. The value found for the basal (repression independent) invertase mRNA was of 45-50 min. The half-life of alpha-glucosidase mRNA was computed following the mathematical procedure described in the Appendix, and a value of 23 min was obtained. These results are consistent with the existence of relatively long-lived RNA messengers involved in the synthesis of extracellular macromolecules.
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PMID:Invertase messenger ribonucleic acid in Saccharomyces cerevisiae. Kinetics of formation and decay. 32 19

Actinomycin D, at a dose of 0.25 micrograms/g body wt, produced slight increases in intestinal enzymatic activity on hamsters. At a high dose (1.5 micrograms/g body wt), actinomycin D produced inhibition of lactase activity, whereas maltase, sucrase and alkaline phosphatase activity decreased in males and increased in females. Cycloheximide (1.5 micrograms/g body wt), produced no changes in enzymatic activity. In the male and female hamster, the different actions of the antibiotic can be explained by the variations in the cortisol release produced by stress.
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PMID:Actinomycin D and cycloheximide actions on activity of some intestinal enzymes of adult hamster. 286 61

Changing patterns of enzyme activity and solute transport in response to washing were investigated in red beet (Beta vulgaris L.) storage tissue. Washing had a pronounced effect on the plasma membrane (PM) H+-ATPase with an increase in both hydrolytic and proton-pumping activities. Immunoblotting indicated that this may be due, in part, to a higher amount of this enzyme in the PM of washed tissue. Activities of the tonoplast (V)H+-ATPase and pyrophosphatase fluctuated during a 4-d washing period, but overall showed no marked change in activity. In tissue discs sucrose (Suc), glucose (Glc), and fructose uptakes increased significantly in response to washing. Cycloheximide, cordycepin, and tunicamycin inhibited both Glc- and Suc-inducible uptake. Monensin also strongly inhibited inducible Glc uptake, but the effect on Suc was less marked. N-Ethylmaleimide inhibited both Suc and Glc uptake, with its effects being more pronounced in fresh tissue. Other protein-modifying reagents showed no significant difference in their level of inhibition between fresh and washed tissue. Transport studies, carried out using energized PM vesicles from fresh and washed tissue, indicated that there was no rise in Suc and Glc uptake rates in response to washing. Results with a range of inhibitors indicated that there was no marked change in transporter sensitivity in vesicles isolated from fresh and washed tissue. The results indicate that the well-described enhancement of solute transport in washed storage tissue may be due to an increased PM H+-ATPase activity rather than to changes in PM carrier activity or to changes in metabolism such as invertase activity.
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PMID:Effects of Prolonged Washing on Primary and Secondary Transport Processes at the Plasma Membrane in Red Beet Storage Tissue. 1222 6

Gibberellic acid (GA(3)) induces invertase activity within 6 hours in Avena stem segments that are incubated in the dark at 23 degrees . The maximum amount of promotion is about 5 times that of invertase activity in untreated segments. GA(3) causes significant promotion of invertase activity at concentrations as low as 3 x 10(-5) mum GA(3). The increase in invertase activity elicited by GA(3) between 3 x 10(-5) mum and 300 mum closely parallels the growth promotion that is caused by GA(3) over this concentration range. In control segments, invertase activity rises steeply during the first 6 hours of incubation, then decays slowly between 12 and 48 hours. In GA(3)-treated segments, the invertase activity also rises during the first 6 hours, parallel to that in control segments and continues to rise during the next 42 hours. These changes in invertase activity during 48-hour incubation periods do not parallel the changes in growth that occur in control and GA(3)-treated segments. Cycloheximide at 10 mug/ml abolishes all GA(3)-promoted growth and invertase activity in these segments. Actinomycin D at 40 and 80 mug/ml decreases GA(3)-promoted growth by 20% and invertase activity by 38 and 44%, respectively. The data clearly support the idea that protein synthesis is necessary for GA(3)-promoted growth and invertase activity in Avena stem segments.
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PMID:Promotion of growth and invertase activity by gibberellic Acid in developing Avena internodes. 1665 32

The activity of invertase and its relation to growth were studied in the epicotyls of lentil seedlings incubated in the presence and absence of gibberellic acid (GA(3)).Invertase activity per epicotyl increases relatively more rapidly than does length, reaches a maximum during most active elongation, and declines upon cessation of growth.GA(3) enhances both growth and increase in invertase activity, without altering the kinetics of the 2 processes. If GA(3) is added during incubation invertase activity increases more rapidly than does elongation rate.Incubation of the seedlings in solutions of polyethyleneglycol inhibits the increase of both growth and invertase activity, the latter actually undergoing a decline, but causes no great change in the relative effect of GA(3). In presence of polyethyleneglycol GA(3) has however a relatively greater effect on invertase activity than on growth.Sugars in the incubation medium have no significant effect on growth and invertase activity in the epicotyl, except inhibition at relatively high concentrations.Cycloheximide, actinomycin D, and 5-fluorodeoxyuridine (FUDR) inhibit both growth and the increase in invertase activity. Added during incubation cycloheximide causes complete inhibition of growth and a decrease in invertase activity with no appreciable lag phase. With actinomycin D and FUDR the inhibition occurs after lag periods of 2 to 3 and of at least 10 hours, respectively. Thus the increase in enzyme activity is very probably based on de-novo synthesis, and the enzyme is in a state of turnover during growth.The enzyme is present in soluble form in the cytoplasm, not firmly bound to any cell structures.
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PMID:Invertase activity and cell growth in lentil epicotyls. 1665 85

Gibberellic acid and sucrose play significant roles in the increases in invertase and growth in Avena stem segments. About 80% of invertase is readily solubilized, whereas the rest is in the cell wall fraction. The levels of both types of invertase change in a similar manner in the response to gibberellic acid and sucrose treatment. The work described here was carried out with only the soluble enzyme. In response to a treatment, the level of invertase activity typically follows a pattern of increase followed by decrease; the increase in activity is approximately correlated with the active growth phase, whereas the decrease in activity is initiated when growth of the segments slows. A continuous supply of gibberellic acid retards the decline of enzyme activity. When gibberellic acid was pulsed to the segments treated with or without sucrose, the level of invertase activity increased at least twice as high in the presence of sucrose as in its absence, but the lag period is longer with sucrose present. Cycloheximide treatments effectively abolish the gibberellic acid-promoted growth, and the level of enzyme activity drops rapidly. Decay of invertase activity in response to cycloheximide treatment occurs regardless of gibberellic acid or sucrose treatment or both, and it is generally faster when the inhibitor is administered at the peak of enzyme induction than when given at its rising phase. Pulses with sucrose, glucose, fructose, or glucose + fructose elevate the level of invertase significantly with a lag of about 5 to 10 hours. The increase in invertase activity elicited by a sucrose pulse is about one-third that caused by a gibberellic acid pulse given at a comparable time during mid-phase of enzyme induction, and the lag before the enzyme activity increases is nearly twice as long for sucrose as for gibberellic acid. Moreover, the gibberellic acid pulse results in about three times more growth than the sucrose pulse. Our studies support the view that gibberellic acid, as well as substrate (sucrose) and end products (glucose and fructose), play a significant role in regulating invertase levels in Avena stem tissue, and that such regulation provides a mechanism for increasing the level of soluble saccharides needed for gibberellic acid-promoted growth.
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PMID:Regulation of invertase levels in Avena stem segments by gibberellic Acid, sucrose, glucose, and fructose. 1665 35

Previously we showed that acid invertase activity increased and then decreased rapidly in wounded sweet potato (Ipomoea batatas Liam.) root tissue, and that the tissue contained a heat-stable, proteinaceous inhibitor with a molecular weight of about 19,500 daltons.In response to wounding of sweet potato root tissue, inhibitor activity decreased during the increase in invertase activity but later increased slightly when invertase activity declined. Cycloheximide treatment did not affect the decrease in inhibitor activity that occurred during the early incubation stage, but did inhibit the increase in inhibitor activity that occurred during the late incubation stage. Intrinsic invertase activity, which was assayed after removing the inhibitor, increased and then decreased after wounding, as apparent activity did.The degradative rate of acid invertase in root discs, when assayed by intrinsic activity, was roughly the same during both the early and late incubation stages after wounding, and the degradative rate of the enzyme during the late incubation stage was unaffected by cycloheximide treatment. These results suggest that in sweet potato root discs, enzyme synthesis occurs during the early incubation stage, and ceases during the late incubation stage; however, the enzyme undergoes constant degradation.The change in acid invertase activity after wounding seems to be controlled in root tissue by the interactions of inhibitor-binding and turnover of the enzyme protein.
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PMID:Synthesis and apparent turnover of Acid invertase in relation to invertase inhibitor in wounded sweet potato root tissue. 1665 60

Excised primary leaf blades of barley (Hordeum vulgare L. cv Gerbel) rapidly synthesized large quantities of fructan in the light and, upon transfer to the dark, they rapidly degraded it again. In the course of such a light/dark cycle the activities of sucrose-sucrose-fructosyltransferase (SST), fructan hydrolase, and invertase were measured in cell-free extracts of the blades. SST activity increased 20-fold within 24 hours in the light and disappeared again upon transfer to the dark during a similar period of time. Cycloheximide inhibited the increase of SST activity in the light indicating de novo synthesis. The loss of SST activity in the dark, however, was unaffected by cycloheximide. No SST activity appeared in the light if photosynthesis was inhibited by lowering the CO(2) concentration in the atmosphere. However, SST activity and fructan synthesis were induced even in the dark and at a low CO(2) concentration when the leaf blades were immersed in a solution of sucrose. Several other sugars, maltose and fructose in particular, had the same effect. Trehalose induced SST activity but no fructan synthesis occurred. The activities of fructan hydrolase and invertase changed little during the light/dark cycle. It is suggested that the control of SST activity in conjunction with the supply of photosynthates plays a key role in the regulation of fructan metabolism.
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PMID:Regulation of Fructan Metabolism in Leaves of Barley (Hordeum vulgare L. cv Gerbel). 1666 35