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At least 37 records · Page 2Linked to original sources
PubMed1983

[Methodologic studies on protein metabolism and bioenergetics of protein deposition in growing animals. 4. Energy metabolism in chickens in connection with measurement of parameters of protein metabolism].

In connection with the measuring of parameters of the protein metabolism in parallel experiments, the energy metabolism of 6 chickens (origin Tetra B) in the live weight range between approximately 100 and 1,800 g was determined under conditions of restricted energy supply. 3 animals each received a feed mixture containing 20% (animal group 1) and 38% (animal group 2) crude protein. The amount of feed was daily increased by 1.5 g DM. The digestibility of energy and nitrogen was independent of the age. 66.3 +/- 3.3% and 64.0 +/- 5.0% resp. of the metabolisable energy were utilised for protein and fat retention. The energy maintenance requirement, determined at a live weight of 2,000 g, was independent of protein supply and averaged in the two animal groups 434 +/- 40 kJ metabolisable energy/kg live weight 0.75 . d. The result of multiple regression was, for the growth period investigated, an energy maintenance requirement of 403 +/- 32 kJ metabolisable energy/kg live weight 0.75 . d. 1.77 and 1.38 J metabolisable energy resp. were required for 1 J protein or fat retention. The energy requirement for protein retention was independent of the degree of protein supply. The results from the measuring of energy metabolism are discussed in connection with the kinetic parameters of protein metabolism ascertained in parallel experiments.

Animals↗
PubMed1993

[Ethanol metabolism and pathobiochemistry of organ damage--1992. II. Relation between ethanol metabolism and free radicals, and the metabolism of saccharides and amino acids. Ethanol as a carcinogen. Drug interactions with ethanol].

Ethanol metabolism induces formation of free radicals which are responsible for lipid peroxidation of biological membranes with subsequent aldehyde formation (malondialdehyde,4-hydroxy-nonenal). These aldehydes are competitive or mixed inhibitors of aldehyde dehydrogenase, and they cause an increase in hepatocellular toxicity of aldehydes. The activity of antioxidative systems in human body after chronic as well as acute ethanol intake is being reduced. Interference of ethanol metabolism and gluconeogenesis is caused by inhibition of intake substrates or by decrease NADH/NAD+, ratio in hepatocyte. The blood level of glucose decreases, lactate level increases as well as the ration of lactate, pyruvate and NADH/NAD+ which inhibit cytosole pyruvate carboxykinase. An acute ethanol administration reduces the concentration of most amino acids in plasma by ethanol oxidation impacts on increase of NADH/NAD+ ratio or by mechanism mediated by beta-adrenergic receptors. Chronic alcoholics develop tolerance to decreased plasmatic levels of amino acids. Accumulation of proteins in liver may be explained by larger amount of proteins binding to fatty acids, and also by diminished degradation of proteins with decreasing autophagosome and autolysosome formations. Alcohol is one of carcinogenic factors. Ethanol, acetaldehyde and originating free radicals impaired the DNA repairing enzyme. Binding itself to DNA, acetaldehyde changes DNA properties. Ethanol may also function as a co-carcinogen due to its ability to increase disolution and absorption of carcinogens. Chronic alcoholism induces cytochrome P450 which takes part in the activation and metabolism of carcinogens. Mutual interaction of drugs metabolism and ethanol is connected mainly with cytochrome P450-MEOS. Acute ethanol intake inhibits MEOS, as MEOS gives preference to ethanol as a substrate, however, chronic alcoholism induces MEOS.(ABSTRACT TRUNCATED AT 250 WORDS)

Alcoholism↗
PubMed1991

Extremely slow metabolism of amitriptyline but normal metabolism of imipramine and desipramine in an extensive metabolizer of sparteine, debrisoquine, and mephenytoin.

A 34-year-old man with bipolar manic depressive illness suffered from severe adverse effects during treatment with amitriptyline, 50 mg/day. It was subsequently shown that the patient was a slow metabolizer of amitriptyline. However, he tolerated a dose of 200 mg of imipramine/day, which was necessary in order to reach a therapeutic level of about 900 nM for imipramine plus desipramine. Since both antidepressants are subject to the genetic sparteine/debrisoquine oxidation polymorphism, the patient was phenotyped with sparteine. The test performed during paroxetine treatment indicated that the patient was a poor metabolizer. Subsequent tests performed during a drug-free period, however, showed the patient to be an extensive metabolizer, with a sparteine metabolic ratio (MR) of 1.7 and 2.8 and debrisoquine MR of 2.3. It was subsequently shown that paroxetine is a potent, competitive inhibitor of 1'-hydroxybufuralol formation in a human liver microsome preparation (K1 approximately 800 nM). This patient thus illustrates two problems: (a) the erroneous phenotyping due to concurrent medication, and (b) the existence of a very slow amitriptyline elimination apparently not related to the sparteine/debrisoquine oxidation polymorphism.

Administration, Oral↗
PubMed2004

[New aspects of hexobarbital metabolism: stereoselective metabolism, new metabolic pathway via GSH conjugation, and 3-hydroxyhexobarbital dehydrogenases].

Hexobarbital, a short-acting hypnotic, is metabolized to 3'-hydroxyhexobarbital by cytochrome P450, and then to 3'-oxohexobarbital by liver cytosolic dehydrogenase. New methods of separation for hexobarbital and its metabolites by TLC have been developed and applied to study the metabolism of hexobarbital enantiomers and stereoselective metabolism of hexobarbital. (+)-Hexobarbital preferentially was transformed into beta-3'-hydroxyhexobarbital and the (-)-enantiomer preferentially transformed into alpha-3'-hydroxyhexobarbital by rat liver microsomes. Glucuronidation and dehydrogenation of 3'-hydroxyhexobarbital were also stereoselective and the S-configuration at the 3'-position was preferred. Alpha-3'-hydroxyhexobarbital from (-)-hexobarbital and the beta-isomer from (+)-hexobarbital were shown to be preferentially conjugated with glucuronic acid in rabbit urine, and to be preferentially dehydrogenated to form 3'-oxohexobarbital by rabbit and guinea pig 3-hydroxyhexobarbital dehydrogenases. A new metabolic pathway of hexobarbital was found in which 3'-oxohexobarbital reacts with glutathione to form 1,5-dimethylbarbituric acid and a cyclohexenone-glutathione adduct, a novel metabolite. 1,5-dimethylbarbituric acid was excreted into the urine and the cyclohexenone-glutathione adduct into the bile of rats dosed with hexobarbital. 3-hydroxyhexobarbital dehydrogenases that dehydrogenate 3-hydroxyhexobarbital into 3'-oxohexobarbital were purified from the liver cytosol of rabbits, guinea pigs, goats, rats, mice, hamsters, and humans and characterized. These enzymes were monomeric proteins and had molecular weights of about 34500-42000, and used NAD(+) and NADP(+) as cofactors, except for the human enzyme that had a molecular weight of about 58000 and used NAD(+) alone. Each enzyme exhibited its own characteristics. Substrate specificity demonstrated that 3-hydroxyhexobarbital dehydrogenases dehydrogenate not only alpha,beta-unsaturated cyclic and acyclic secondary alcohols but also some 17 beta-, 3 alpha-hydroxysteroids or both, except for the human enzyme. The amino acid sequence of the hamster enzyme indicated that it belongs to the aldo-keto reductase superfamily and hydroxysteroid dehydrogenase subfamily.

Alcohol Oxidoreductases↗
PubMed1991

Age-related changes in metabolism of diethofencarb: relationship between metabolism in rat and hepatic drug-metabolizing enzyme activities.

1. Age-related changes in metabolism of diethofencarb (DFC) (isopropyl-1,4-diethoxycarbanilate) and hepatic drug-metabolizing enzyme activities were studied in male Sprague-Dawley rats aged 2, 8, 16 and 21 months. 2. Following a single oral dose of 14C-DFC (500 mg/kg), the major route of elimination of the 14C for 7 days was urine (85.6-97.8%) at all ages. 3. Analysis of urinary metabolites showed that deethylation of 14C-DFC was constant for all age groups; however, sulphation and acetylation significantly decreased, and glucuronidation increased, with age. 4. Hepatic PAPS-sulphotransferase and acetyl-CoA: N-acetyltransferase in DFC metabolism significantly decreased with age, whereas no significant effects of ageing on O-deethylase and UDP-glucuronyltransferase were observed. 5. Results show that age-related differences in the ratios of urinary metabolites of DFC resulted to some extent from changes in the hepatic drug-metabolizing enzyme activities.

Aging↗
PubMedDate not supplied

[Metabolic indices for the bone tissue organic base metabolism and its mineral metabolism in patients with scoliosis].

The biochemical findings secured in the examination of 55 pediatric patients presenting with a progressing form of scoliosis suggested to us abnormalities of metabolism in the osseous tissue organic base and of the mineral metabolism. Indices capable of reflecting in the most unbiassed fashion the osseous tissue metabolic states include Ca/Cr, Ca/fr OP, Ph/Cr, Ph/fr OP ratios. Collagen and mineral metabolic disturbances result in structural changes in the vertebral osseous tissue organic base that may have an important part in the development of scoliotic disease.

Absorptiometry, Photon↗
PubMed1992

Dynamic metabolic control theory. A methodology for investigating metabolic regulation using transient metabolic data.

The purposes of the dynamic metabolic control theory are to provide a theoretical basis for estimating the control coefficients using the transient metabolic responses and to gain insights into the metabolic regulation in the transient states. The numerical application of this theory is relatively straightforward: it involves a standard linear regression and a matrix multiplication. Although the equations are exact only for linear kinetics, they yield relatively good estimates of the control coefficients for nonlinear systems.

Cells↗
PubMed2000

Human 293 cell metabolism in low glutamine-supplied culture: interpretation of metabolic changes through metabolic flux analysis.

Metabolic flux analysis is a useful tool to analyze cell metabolism. In this study, we report the use of a metabolic model with 34 fluxes to study the 293 cell, in order to improve its growth capacity in a DMEM/F12 medium. A batch, fed-batch with glutamine feeding, fed-batch with essential amino acids, and finally a fed-batch experiment with both essential and nonessential amino acids were compared. The fed-batch with glutamine led to a maximum cell density of 2.4x10(6) cells/ml compared to 1.8x10(6) cells/ml achieved in a batch mode. In this fed-batch with glutamine, it was also found that 2.5 mM ammonia was produced compared to the batch which had a final ammonia concentration of 1 mM. Ammonia was found to be growth inhibiting for this cell line at a concentration starting at 1 mM. During the fed-batch with glutamine, the flux analysis shows that a majority of amino acid fluxes and Kreb's cycle fluxes, except for glutamine flux, are decreased. This observation led to the conclusion that the main nutrient used is glutamine and that during the batch there is an overflow in the Kreb's cycle. Thus, a fed-batch with glutamine permits a better utilization of this nutrient. A fed-batch with essential amino acid without glutamine was also assayed in order to reduce ammonia production. The maximum cell density was increased further to 3x10(6) cells/ml and ammonia production was reduced below 1 mM. Flux analysis shows that the cells could adapt to a medium with low glutamine by increasing the amino acid fluxes toward the Kreb's cycle. Adding nonessential amino acids during this feeding strategy did not improve growth further and the nonessential amino acids accumulated in the medium.

Amino Acids↗
PubMed2005

3-chloro-, 2,3- and 3,5-dichlorobenzoate co-metabolism in a 2-chlorobenzoate-degrading consortium: role of 3,5-dichlorobenzoate as antagonist of 2-chlorobenzoate degradation. Metabolism and co-metabolism of chlorobenzoates.

A study was made of the metabolic and co-metabolic intermediates of 2- and 3-chlorobenzoate, 2,3- and 3,5-dichlorobenzoate to elucidate the mechanism(s) involved in the negative effects observed on the growth of a chlorobenzoate-degrading microbial consortium in the presence of mixed chlorobenzoates. 2-Chloromuconate accumulated as the end-product in the cultural broths of the microbial consortium during growth on 2-chlorobenzoate; the same 2-chloromuconate was identified in the reaction mixtures of resting cells pregrown on 2-chlorobenzoate and exposed to 3-chloro- and 2,3-dichlorobenzoate, while in similar experiments 1,2-dihydroxy-3,5-dichloro-cyclohexa-3,5-dienoate was detected as dead-end product of 3,5-dichlorobenzoate co-metabolism. These results suggest an initial degradative attack by 2-chlorobenzoate induced dioxygenase(s). The role of 3,5-dichlorobenzoate as an antagonist of 2-chlorobenzoate degradation was also studied: in the presence of mixed 2-chloro- and 3,5-dichlorobenzoate, the 3,5-dichlorobenzoate preferential uptake by the resting cells of the chlorobenzoate-degrading consortium was observed. 2-Chlorobenzoate entered the cells only after the complete removal of the co-substrate. In growing cells experiments, the addition of 1,2-dihydroxy-3,5-dichloro-cyclohexa-3,5-dienoate, the 3,5-dichlorobenzoate co-metabolite, to 2-chlorobenzoate exerted the same antagonistic effect of the parent compound, inhibiting both the microbial growth and the degradative process. These data are discussed, allowing us to attribute the inhibitory effects observed to a substrate/co-substrate competition, though other additional causes may not be totally excluded.

Bacteria↗
PubMed2006

Cloning and expression analysis of a UDP-galactose/glucose pyrophosphorylase from melon fruit provides evidence for the major metabolic pathway of galactose metabolism in raffinose oligosaccharide metabolizing plants.

The Cucurbitaceae translocate a significant portion of their photosynthate as raffinose and stachyose, which are galactosyl derivatives of sucrose. These are initially hydrolyzed by alpha-galactosidase to yield free galactose (Gal) and, accordingly, Gal metabolism is an important pathway in Cucurbitaceae sink tissue. We report here on a novel plant-specific enzyme responsible for the nucleotide activation of phosphorylated Gal and the subsequent entry of Gal into sink metabolism. The enzyme was antibody purified, sequenced, and the gene cloned and functionally expressed in Escherichia coli. The heterologous protein showed the characteristics of a dual substrate UDP-hexose pyrophosphorylase (PPase) with activity toward both Gal-1-P and glucose (Glc)-1-P in the uridinylation direction and their respective UDP-sugars in the reverse direction. The two other enzymes involved in Glc-P and Gal-P uridinylation are UDP-Glc PPase and uridyltransferase, and these were also cloned, heterologously expressed, and characterized. The gene expression and enzyme activities of all three enzymes in melon (Cucumis melo) fruit were measured. The UDP-Glc PPase was expressed in melon fruit to a similar extent as the novel enzyme, but the expressed protein was specific for Glc-1-P in the UDP-Glc synthesis direction and did not catalyze the nucleotide activation of Gal-1-P. The uridyltransferase gene was only weakly expressed in melon fruit, and activity was not observed in crude extracts. The results indicate that this novel enzyme carries out both the synthesis of UDP-Gal from Gal-1-P as well as the subsequent synthesis of Glc-1-P from the epimerase product, UDP-Glc, and thus plays a key role in melon fruit sink metabolism.

Amino Acid Sequence↗
PubMed2006

Regulation of hormone metabolism in Arabidopsis seeds: phytochrome regulation of abscisic acid metabolism and abscisic acid regulation of gibberellin metabolism.

In a wide range of plant species, seed germination is regulated antagonistically by two plant hormones, abscisic acid (ABA) and gibberellin (GA). In the present study, we have revealed that ABA metabolism (both biosynthesis and inactivation) was phytochrome-regulated in an opposite fashion to GA metabolism during photoreversible seed germination in Arabidopsis. Endogenous ABA levels were decreased by irradiation with a red (R) light pulse in dark-imbibed seeds pre-treated with a far-red (FR) light pulse, and the reduction in ABA levels in response to R light was inhibited in a phytochrome B (PHYB)-deficient mutant. Expression of an ABA biosynthesis gene, AtNCED6, and the inactivation gene, CYP707A2, was regulated in a photoreversible manner, suggesting a key role for the genes in PHYB-mediated regulation of ABA metabolism. Abscisic acid-deficient mutants such as nced6-1, aba2-2 and aao3-4 exhibited an enhanced ability to germinate relative to wild type when imbibed in the dark after irradiation with an FR light pulse. In addition, the ability to synthesize GA was improved in the aba2-2 mutant compared with wild type during dark-imbibition after an FR light pulse. Activation of GA biosynthesis in the aba2-2 mutant was also observed during seed development. These data indicate that ABA is involved in the suppression of GA biosynthesis in both imbibed and developing seeds. Spatial expression patterns of the AtABA2 and AAO3 genes, responsible for last two steps of ABA biosynthesis, were distinct from that of the GA biosynthesis gene, AtGA3ox2, in both imbibed and developing seeds, suggesting that biosynthesis of ABA and GA in seeds occurs in different cell types.

Abscisic Acid↗
PubMed1991

[Determination of kinetic parameters of protein metabolism in growing rats in conjunction with measurement of energy metabolism. 1. Determination of kinetic parameters of protein metabolism in relation to body weight and protein content of the feed].

The digestibility, the N balance, the rate of protein synthesis and other parameters, characterising the protein metabolism in dependence on live weight, protein- and energy supply are estimated on Wistar rats (4-5 animals/group). These experiments were done in 5 alternating consecutive growth and energy maintenance periods at 4 different levels of protein (6, 10, 17, 26% CP) during the live weight period of 70 to 230 g. The rate of protein synthesis was calculated from the course of renale 15N excretion by means of the end product method after giving a single dose of a mixture of 17 15N labelled amino acids. N deposition, rate of protein synthesis and flux rate increased with the protein level of the ration. During maintenance these data were much lower, but showed the same dependence on the protein level. The absolute protein synthesis (g/d) increased up to the live weight of 130... 180 g and decreased afterwards according to the age. The reutilization rate varied between 44 and 87% and decreased with increasing dietary protein level by 27% and during proceeding age by 8 ... 12%. In contrast to the absolute metabolism rates (g/d) the fractional rates (%/d) clearly decreased with the age of the animals. The stimulation of these rates by the dietary protein level resembled that for the absolute rates of synthesis. The protein deposition showed the typical course of a growing curve according to the N intake and the protein synthesis showed practically the same course but on a higher level. The break down remained constantly (approximately 140 mg N/d) up to an N intake of about 360 mg and afterwards it increased too.

Amino Acids↗
PubMed1984

Determinants of acetaminophen metabolism: effect of inducers and inhibitors of drug metabolism on acetaminophen's metabolic pathways.

Acetaminophen metabolism and clearance after a single 1 gm oral dose of the drug was investigated in 12 healthy men, six of whom were cigarette smokers, and in six men who were receiving anticonvulsant drugs for epilepsy. The 12 healthy subjects were studied before and after 1 wk of pretreatment with cimetidine (1 gm/day) or sulfinpyrazone (800 mg/day). There was no significant difference in acetaminophen clearance (ClAP) between nonsmokers and smokers; cimetidine pretreatment had no effect on ClAP. Neither cigarette smoking nor cimetidine pretreatment had a significant effect on any of the metabolic pathways of acetaminophen. In contrast, sulfinpyrazone pretreatment increased ClAP by 23% (from 5.70 +/- 0.21 to 7.00 +/- 0.39 ml/min/kg) and ClAP was 46% greater in the epileptic subjects who received anticonvulsant drugs than in the control group (8.32 +/- 0.45 and 5.70 +/- 0.21 ml/ml/kg). In both cases the increase in ClAP was a result of induction of acetaminophen glucuronidation and oxidation; clearance of the glucuronic acid conjugate was 26% and 59% greater and clearance of the glutathione-derived conjugates (reflecting the activity of the oxidative pathway) was 43% and 60% greater in the groups given sulfinpyrazone and anticonvulsants, respectively.

Acetaminophen↗
PubMed1993

Long-Term Anaerobic Metabolism in Root Tissue (Metabolic Products of Pyruvate Metabolism).

The onset of anaerobiosis in barley root tissue (Hordeum vulgare L. cv Himalaya) results in the following metabolic responses. There are rapid increases in the levels of pyruvate, lactate, and ethanol. Malate and succinate concentrations increase over the first 12 h, after which they return to the levels found in oxygenated root tissue. Alanine concentration increases over the first 12 h, and this is matched by a corresponding decrease in aspartate. The initial stoichiometric decline in aspartate and increase in alanine suggests that the amino group of aspartate is conserved by transaminating pyruvate to alanine. Aspartate catabolism also probably provides the initial source of carbon for reduction to succinate under anoxic conditions. Under long-term anaerobiosis (>24 h), there is no further accumulation of any of the fermentative end products other than ethanol, which also represents the major metabolic end product during long-term anaerobiosis. Although a number of the enzymes involved in fermentative respiration have been found to be induced under anaerobic conditions, neither aspartate amino-transferase nor malate dehydrogenase is induced in barley root tissue. The observations suggest that the long-term adaptations to hypoxic conditions may be quite different than the more well-characterized short-term adaptations.

Journal Article↗
PubMed1980

Carbon Dioxide and Water Vapor Exchange in the Crassulacean Acid Metabolism Plant Kalanchoë pinnáta during a Prolonged Light Period: METABOLIC AND STOMATAL CONTROL OF CARBON METABOLISM.

Net CO(2) and water vapor exchange were studied in the Crassulacean acid metabolism plant Kalanchoë pinnáta during a normal 12-hour light/12-hour dark cycle and during a prolonged light period. Leaf temperature and leaf-air vapor pressure difference were kept constant at 20 C and 9 to 10 millibar. There was a 25% increase in the rate of CO(2) fixation during the first 6 hours prolonged light without change in stomatal conductance. This was associated with a decrease in the intracellular partial pressure of CO(2), a decrease in the stimulation of net CO(2) uptake by 2% O(2), and a decrease in the CO(2) compensation point from 45 to 0 microbar. In the normal light period after deacidification, leaves showed a normal light dependence of CO(2) uptake but, in prolonged light, CO(2) uptake was scarcely light-dependent. The increase in titratable acidity in prolonged light was similar to that in the dark.The results suggest a change from C(3) photosynthetic CO(2) fixation in the second part of the 12-hour light period to a mixed metabolism in prolonged light with both ribulose bisphosphate carboxylase and phosphoenolpyruvate carboxylase as primary carboxylating enzymes.

Journal Article↗
PubMed1991

Metabolic clearance rate of dehydroepiandrosterone sulfate, its metabolism to testosterone, and its intrafollicular metabolism to dehydroepiandrosterone, androstenedione, testosterone, and dihydrotestosterone in vivo.

At the time of surgery, women were infused with [3H]dehydroepiandrosterone sulfate ([3H]DS)/[14C]testosterone ([14C]T) for 6 h; blood samples were obtained from an artery the ovarian veins, and a peripheral vein; and fluid was obtained from ovarian follicles. Both blood and follicular fluid samples were analyzed for radioactivity as DS, dehydroepiandrosterone (D), androstenedione (delta 4A). T, and dihydrotestosterone (DHT), and the blood was also analyzed for the concentration of nonisotopic DS by RIA. In other subjects the concentrations of D and DS were measured in paired samples of blood and follicular fluid. From these data, values of 13.6 +/- 0.69 L/day four (mean +/- SE; n = 4) for MCRDS, 607 +/- 90 L/day (n = 3) for MCRT, and 0.0190 +/- 0.0089 (n = 3) for [p]DS-T (fraction of plasma DS metabolized to plasma T) were obtained. The ratio of the concentration of the tracer-labeled steroid in the follicular fluid to the concentration in the arterial plasma sample was elevated significantly above 1 for three 3H-labeled and three [14C-labeled metabolites: [3H]D (21-fold; P less than 0.001), [3H]T (81-fold; P less than 0.001), [3H]DHT (19-fold; P less than 0.001), [14C]T (4-fold; P less than 0.025), [14C]DHT (21-fold; P less than 0.01), and [14C]delta 4A (50-fold; P less than 0.001). The estimated concentrations of steroids in follicular fluid derived from DS based on specific activity calculations were as follows: [geometric mean (95% confidence limits; n)]: DS, 5600 (4800-6500 nmol/L; 12); D, 370 (88-1500 nmol/L; 10); delta 4 A, 120 (67-220 nmol/L; 12); T, 130 (39-450 nmol/L; 10); and DHT, 64 (35-120 nmol/L; 8). Comparison of these data to known follicular fluid steroid concentrations shows that DS from the intravascular pool can be used as an ovarian prehormone.

Adult↗
PubMed2002

Complexities in ETS-domain transcription factor function and regulation: lessons from the TCF (ternary complex factor) subfamily. The Colworth Medal Lecture.

The ETS-domain transcription factor family can be divided into a series of subfamilies. Elk-1 represents the founding member of the ternary complex factor (TCF) subfamily. By focusing on the TCF subfamily, we can demonstrate the complexities that exist in the function and regulation of ETS-domain transcription factors. This article focuses on Elk-1 in detail and summarizes the functions of other TCFs. The key themes covered include the domain structure of the TCFs, the mechanisms of complex formation with serum response factor, regulation of TCFs by mitogen-activated protein kinase cascades, and transcriptional regulatory properties of the TCFs. Finally, the emerging role of the TCFs in vivo is discussed. A picture is developing indicating that, while these proteins exhibit significant sequence and functional conservation, key differences in their structure and regulation are being identified which may relate to unique functions of these proteins in vivo.

Amino Acid Sequence↗