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At least 19 recordsLinked to original sources
PubMedDate not supplied

[Effect of IAA on the content of RNA in the cells and isolated nuclei of Aspergillus oryzae].

The content of RNA in mycelium and isolated nuclei of Aspergillus oryzae 3-9-15 was studied after its growth during two days on the modified Capek medium containing 0.01 and 10 mg% of IAA. A direct correlation has been established between the extracellular concentration of IAA and its content in the mycelium and isolated nuclei of the fungus. The stimulating effect of the extracellular IAA on the content of RNA in the isolated nuclei was optimal after one hour of incubation in the Capek medium containing 0.01 or 10 mg% of IAA.

Aspergillus↗
PubMed1977

A scanning electron microscopic study of IAA-induced tumors in bean (Phaseolus vulgaris L.) embryos.

A scanning electron microscopic study of indole-3-acetic acid (IAA) induced tumour in the hypocotyl region of bean embryos shows a distinct morphological, structural and topographical change from the non-treated bean embryos. The IAA-induced tumour surface, in the hypocotyl region, shows distinct cell enlargement, some cellular proliferation in the parenchymatous tissue, total destruction of the epidermis and stomata and some variation in trichome structures. In dole-3-acetic acid inhibits the normal growth of the epicotyl, and, as age progresses, adventitious roots appear all over the surface. When IAA-depletion occurs, epicotyl growth resumes, which indicates that this tumour formation in bean embryos is an IAA-dependent tumour.

Indoleacetic Acids↗
PubMed1978

Cytological study of inhibitory effects of IAA on the root growth in the Pinus silvestris.

It has been found that IAA at the concentrations 0.1--10.0 ppm retards the pine root growth and decreases mitotic activity. All the applied concentrations of this hormone cause a decrease of the 3H-thymidine incorporation index and inhibit endomitotic polyploidization in suprameristematic segments. The mean time of the cell cycle prolongs and the heterogeneity of cellular populations increases in parallel with the increase of IAA concentration. The template activity of DNA decreases under the influence of the applied concentrations of IAA; this effect is being particularly strong in the meristematic root segment. IAA exerts also an inhibitory influence on protein synthesis, especially reducing the synthesis of histones.

DNA↗
PubMed1992

Cloning of a promoter-like soybean DNA sequence responding to IAA induction in Escherichia coli K12.

We have constructed a soybean genomic DNA library in Escherichia coli K12 strain KC13 using plasmid pPV33, which consists of a promoter-less tetracycline resistance (Tcr) gene. A recombinant clone, KC13(pAU-SB1)+, was obtained by selecting for resistance to tetracycline in the presence of indole-3-acetic acid (IAA). Restriction enzyme cleavage and Southern hybridization analysis revealed that the pAU-SB1 plasmid has a 250 bp soybean DNA insert fused with the Tcr gene. In the presence of a selected group of auxins, induction of the Tcr phenotype and mRNA synthesis of the Tcr gene are observed only in KC13(pAU-SB1)+ cultures. On the other hand, induction of the Tcr phenotype and mRNA synthesis of the Tcr gene are absent in cells harboring the cloning vector pPV33 or a recombinant plasmid containing the 250 bp insert in the reverse orientation, pAU-SB1ro. This demonstrated a need for the insertion of the 250 bp soybean DNA and the specificity of its orientation in response to IAA induction. The start point of mRNA transcription in response to IAA, IBA, IPA, 2,4,5-T, and a-NAP is at base pair -96 or -95 upstream of the translational start site of the Tcr gene and base pair -98 with 2,4-D.

Base Sequence↗
PubMed1992

Indole-3-acetic acid (IAA) production by Arthrobacter species isolated from Azolla.

Arthrobacter species, isolated from the leaf cavities and the microsporocarps of the aquatic fern species Azolla pinnata and Azolla filiculoides, produced indole-3-acetic acid (IAA) in culture when the precursor tryptophan was added to the medium. No IAA production was detected in the absence of tryptophan. Maximum IAA formation was obtained in the first 2 d of incubation. Part of the tryptophan was transformed to N alpha-acetyl-L-tryptophan.

Arthrobacter↗
PubMedDate not supplied

[Effect of IAA on the photophosphorylation of pea isolated chloroplasts].

Effect of IAA (10(-10)-10(-3) M) on photophosphorylation, NADP reduction and the oxygen exchange is investigated. It is shown that low concentrations of IAA (10(-10)-10(-7) M) increase the photophosphorylation reaction and the flow of electrones to NADP under the phosphorylation conditions in the chloroplasts, and their effect on the O2 exchange is not the same in different types of photophosphorylation. It is supposed that the effect of IAA on the photophosphorylation is connected with H292 metabolism in chloroplasts and with catalase and peroxidase functions.

Chloroplasts↗
PubMed2026

QPL-enabled HTSlib library: accelerating sequence file compression using Intel IAA.

SUMMARY: Sequence analysis workflows require the accessibility of large datasets, which require state-of-the-art compression tools. These compression tools, such as Samtools, often rely on HTSlib as a GZip implementation, but are still limited by throughput on time-intensive compression. QPL-HTSLib offers order of magnitude speedups for the compression and decompression of the SAM and BAM file formats commonly used in genomics workflows at the cost of a slightly larger compressed file, and is a drop-in replacement for HTSlib on Intel systems. AVAILABILITY AND IMPLEMENTATION: QPL-HTSLib is freely available on Github as an open-source software project.

Journal Article↗
PubMed1976

Inhibition of IAA-induced elongation in Avena coleoptile segments by lead: a physiological and an electron microscopic study.

A high resolution growth measuring apparatus was used to demonstrate the inhibition of auxin-induced cell elongation in oat coleoptile segments (Avena sativa L. var Holden) by lead at concentrations ranging from 2 x 10-6 M to 2 x 10-3 M. The inhibition was immediate, having no measurable lag period. Electron micrographs of lead-treated and control segments revealed that in the treated material, lead became localized as electron-dense granules in the cell walls and in vesicles associated with dictyosomes. These granules were found to be lead hydroxide phosphate by electron diffraction techniques. The possible significance of this localization and identification with regard to phosphatase activity is discussed.

Cell Wall↗
PubMed1992

Continuing evolution of the pelvic pouch procedure.

The results of the pelvic pouch procedure were reviewed to assess the surgical complication rate and outcome of patients who had had the procedure performed with a stapled ileo-anal anastomosis with and without a defunctioning ileostomy. Between December 1982 and March 1992, 483 patients underwent a pelvic pouch (PP) procedure. Patients were divided into three groups: group I consisted of 325 patients (178 men and boys and 147 women and girls) who underwent a PP procedure with a handsewn ileoanal anastomosis (IAA) with a defunctioning loop ileostomy. In group II, there were 87 patients (47 men and boys and 40 women and girls) who had a stapled IAA with a defunctioning ileostomy. Group III patients consisted of 71 patients (43 men and boys and 28 women and girls) who had a stapled IAA with no covering ileostomy. Assessment was made of the IAA leak rate, the surgical complications, the reoperation rate, and functional outcome. Early surgical complications included 40 (12%) IAA leaks in group I patients compared with only six (7%) leaks in group II patients who had a stapled IAA (p < 0.05). In group III patients, who had a stapled IAA but no covering ileostomy, there were 13 leaks (18%). Eleven of these 13 leaks healed spontaneously with tube drainage; one patient remains with a rectal tube in place 6 weeks after operation, and only one patient has required a reoperation (defunctioning ileostomy). Functionally, all patients with a healed IAA after a leak have had an excellent result comparable to those without a leak. Patients who were male, older than age 40, on steroids, and had had a true one-stage PP procedure, had a greater risk of developing an IAA leak. In two patients, there was intraoperative difficulty, and one of these patients had an IAA leak after operation. Disease activity at the resection margin and patient weight did not affect the leak rate. Our results suggest that the IAA leak rate is significantly reduced in patients with a stapled IAA with an ileostomy compared with those with a handsewn IAA. Omission of the defunctioning ileostomy is associated with a higher IAA leak rate, but spontaneous healing occurs in almost all patients without impairment of functional results. In patients in whom the ileostomy is omitted, the IAA leak rate is greatest in male patients who have undergone a true one-stage PP procedure, are on steroids, and are older than age 40.

Adenomatous Polyposis Coli↗
PubMed1979

Insulin release and eflux of [32P]Phosphate from islets of rat Langerhans treated with iodoacetic acid and the anomers of D-glucose.

To clarify the insulin-releasing mechanism, we studied insulin release and the efflux of [32P]phosphate by glucose at 0.1 mM/min of gradient level or at 16.7 mM, and other metabolism in islets of rat Langerhans. When treated with 1 mM iodoacetic acid (IAA) plus the anomers of D-glucose at 2.8 mM for 6 min at 37 degrees C, islets elicited insulin at half the control rate under the step-wise stimulation by glucose and at the same rate as the control under the slow-rise stimulation by glucose. Using islets treated with IAA plus the alpha anomer at 16.7 mM, the step-wise stimulation secreted insulin at half a rate of the control and the slow-rise stimulation at the rate lower than the control, which was not significantly different from the control rate. Treatment with IAA plus the beta anomer at 16.7 mM inhibited insulin release under both types of stimulations by glucose. The step-wise stimulation caused the same rapid efflux of [32P]phosphate from IAA-treated islets as from the control islets, except for islets treated with IAA plus the beta anomer at 16.7 mM. The rate of glucose utilization in islets was inhibited by all IAA-treatments to the same extent, being merely half the control rate. Treatments with IAA plus the anomers at 16.7 mM significantly reduced the formation of [3H]-cAMP and the activity of protein phosphokinase in islets, while in the presence of the anomers at 2.8 mM IAA produced no significant effect. Neither IAA-treatments altered the uptake of 45Ca and the ATP content in islets. The uptake of [14C]IAA was significantly enhanced by the presence of the beta anomer at 16.7 mM to two times the control level. On the basis of these results, we suggested that the B cell might contain both glucoreceptors and rate-sensors of glucose controlling insulin release and the former might be less sensitive to IAA as compared with the latter.

Animals↗
PubMed1979

The mechanism of indole-3-acetic acid oxidation by horseradish peroxidases.

The oxygen-consuming oxidation of indole-3-acetic acid (IAA) occurred much faster in the presence of horseradish peroxidase C (neutral isoenzyme) than in the presence of horseradish peroxidase A (acidic isoenzyme). An intermediate oxidation product of IAA was found to be a hydroperoxide species that reacted with the ferric enzymes to form Compound I at second order rate constants of 6.8 X 10(3) M-1--S-1 for peroxidase A and 2.0 X 10(6) M-1--S-1 for peroxidase C at pH 4.4 The hydroperoxide concentration reached about one-half of the initial IAA concentration at the end of the oxygen-consuming reaction and then decreased slowly. The main intermediate of the enzyme observed during the oxygen-consuming reaction was Compound II, which oxidized IAA to its free radical at rate constants of 1.5 X 10(3) M-1--S1 for peroxidase A and 1.2 times 10(4) M-1--S-1 for peroxidase C at pH 4.4 The results supported the mechanism that the oxygen consumption occurs mainly through the reaction of oxygen with the IAA free radical formed from the peroxidatic oxidation of IAA. The ferric enzymes were not reduced by IAA under strict anaerobic conditions in the presence of carbon monoxide but were reduced upon addition to a small amount of oxygen or hydrogen peroxide to the systems. The results suggested that the ferric enzyme is reduced by the IAA free radical but not by IAA itself. From a comparison of reactivities of oxyperoxidase and Compound II we concluded that the catalytic cycle of ferrous and oxyperoxidases is not involved in the IAA oxidase reaction.

Horseradish Peroxidase↗
PubMed1992

Autoantibodies to insulin have similar affinity to that of antibodies to exogenous insulin but lower binding capacity.

The binding characteristics of insulin autoantibodies (IAA) were compared with those of antibodies to exogenous insulin (IBA) by analyzing the specific binding, binding capacity and affinity for insulin in 11 children (age range 1.5-13.0 years) with insulin-dependent diabetes (IDDM) both at diagnosis and after 1 year of insulin treatment. Maximal specific insulin binding was 7.8 (1.5; SE) pmol l-1 for IAA and 28.1 (6.7) pmol l-1 for IBA (P < 0.01), and the binding capacity of the high affinity class of IAA 0.01 (0.003) nmol l-1, as compared with 0.19 (0.08) nmol l-1 for the corresponding IBA class (P < 0.01). With regard to the low-affinity components the binding capacity was 0.11 (0.05) nmol l-1 for IAA and 1.50 (0.95) nmol l-1 for IBA (P < 0.01). No differences in the affinity constants could be observed between IAA and IBA. There was no correlation between the insulin binding of IAA and quantitative levels of islet cell antibodies (ICA) at the clinical presentation or subsequent IBA values. The specific insulin binding of IBA correlated negatively with serum C-peptide concentrations and positively with HbA1 levels at 1 year. The present observations suggest that IAA developing before the diagnosis of IDDM are characterized by a reduced binding capacity as compared with antibodies to exogenous insulin, whereas they have a similar affinity for insulin. IAA seem to be quantitatively unrelated to ICA and postdiagnostic IBA levels. High IBA levels appear to be associated with reduced endogenous insulin secretion and poor metabolic control during the early clinical course of the disease.

Adolescent↗