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1.
Biol Sport ; 40(3): 767-774, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37398959

RESUMEN

This study aimed to verify the time course recovery of muscle edema within the quadriceps femoris and functional performance after lower-body single- and multi-joint exercises. For this within-participant unilateral and contralateral experimental design, fourteen untrained young males performed a unilateral knee extension exercise (KE), and a unilateral leg press (LP) exercise in a counterbalanced order. At pre-, post-, 24 h, 48 h, 72 h, and 96 h after exercise, the peak torque (PT), unilateral countermovement jump (uCMJ) performance, and rectus femoris (RF) and vastus lateralis (VL) muscle thicknesses were recorded in both legs. The PT decreased immediately after (p = 0.01) both exercises (KE and LP) and was fully recovered 24 h after KE (p = 0.38) and 48 h after LP (p = 0.68). Jump height and power, in the uCMJ, followed the same PT recovery pattern after both exercises. However, vertical stiffness (Kvert) was not affected at any time point after both protocols. The RF thickness increased after both exercises (p = 0.01) and was fully restored 48 h after KE (p = 0.86) and 96 h after LP (p = 1.00). The VL thickness increased after both exercises (p = 0.01) and was fully restored 24 h after LP (p = 1.00) and 48 h after KE (p = 1.00). The LP exercise, compared to KE, induced more prolonged impairment of functional performance and delayed recovery of RF muscle edema. However, the VL edema-induced muscle swelling recovery was delayed after the KE exercise. The different recovery kinetics between functional performance and muscle damage should be taken into consideration depending on the objectives of the next training sessions.

2.
Percept Mot Skills ; 117(3): 682-95, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24665790

RESUMEN

This study compared two different rest intervals (RI) between sets of resistance exercise. Ten resistance-trained men (M age = 24.3, SD = 3.5 yr.; M weigh t= 80.0 kg, SD = 15.3; M height = 1.75 m, SD = 0.04) performed five sets of Smith machine bench presses at 60% of one repetition maximum, either with 1.5 min. or 3 min. RI between sets. Their repetition performance, total training volume, velocity, fatigue, rating of perceived exertion, and muscular power were measured. All of these measures indicated that performance was significantly better and fatigue was significantly lower in the 3 min. RI as compared with the 1.5 min. RI, except the rating of perceived exertion which did not show a significant difference. A longer RI between sets promotes superior performance for the bench press.


Asunto(s)
Rendimiento Atlético/fisiología , Entrenamiento de Fuerza/métodos , Adulto , Imagen Corporal/psicología , Prueba de Esfuerzo/métodos , Humanos , Masculino , Fatiga Muscular/fisiología , Entrenamiento de Fuerza/instrumentación , Descanso/fisiología , Autoimagen , Factores de Tiempo , Adulto Joven
3.
Comput Psychiatr ; 6(1): 166-188, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-38774776

RESUMEN

Although evidence suggests that antidepressants are effective at treating depression, the mechanisms behind antidepressant action remain unclear, especially at the cognitive/computational level. In recent years, reinforcement learning (RL) models have increasingly been used to characterise the roles of neurotransmitters and to probe the computations that might be altered in psychiatric disorders like depression. Hence, RL models might present an opportunity for us to better understand the computational mechanisms underlying antidepressant effects. Moreover, RL models may also help us shed light on how these computations may be implemented in the brain (e.g., in midbrain, striatal, and prefrontal regions) and how these neural mechanisms may be altered in depression and remediated by antidepressant treatments. In this paper, we evaluate the ability of RL models to help us understand the processes underlying antidepressant action. To do this, we review the preclinical literature on the roles of dopamine and serotonin in RL, draw links between these findings and clinical work investigating computations altered in depression, and appraise the evidence linking modification of RL processes to antidepressant function. Overall, while there is no shortage of promising ideas about the computational mechanisms underlying antidepressant effects, there is insufficient evidence directly implicating these mechanisms in the response of depressed patients to antidepressant treatment. Consequently, future studies should investigate these mechanisms in samples of depressed patients and assess whether modifications in RL processes mediate the clinical effect of antidepressant treatments.

4.
Int J Exerc Sci ; 13(3): 597-606, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32509119

RESUMEN

The objective of this study was to compare the effects of very high supervision (VHS-RT) versus high supervision (HS-RT) ratio resistance training (RT) on irisin, brain-derived neurotrophic factor (BNDF), muscle strength, functional capacity, and body composition in elderly women. Participants performed daily undulating periodized RT over 16 weeks with two different supervision ratios: VHS-RT at 1:2 (supervisor/subject) or HS-RT at 1:5. Serum was used to analyze brain derived neurotropic factor (BDNF) and irisin by enzyme-linked immunosorbent assay (ELISA). Body composition was evaluated by dual-energy X-ray absorptiometry, while functional capacity was evaluated using the Six-minute walk test, and Timed Up and Go (TUG). One- repetition maximum (1RM) was determined for bench press and 45° leg press exercises. For both groups, no differences between baseline and post-training were identified for irisin and lean mass (p > 0.05). Both groups improved bench press 1-RM, 45° leg press 1-RM, and TUG (p < 0.05). The VHS-RT group displayed higher effect sizes for 1-RM tests. Moreover, only VHS-RT group reduced body fat and body fat percentage (p < 0.05). In contrast, the HS-RT increased BDNF (p < 0.01). In this sense, RT enhances muscle strength and functional capacity in elderly women independent of supervision ratio. A greater supervision ratio during RT may induce more improvements in muscle strength, and body composition than lower supervision ratio during RT.

6.
Mol Cell Biol ; 8(5): 2125-31, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-3290650

RESUMEN

The transcriptional activator ADR1 from Saccharomyces cerevisiae is a postulated DNA-binding protein that controls the expression of the glucose-repressible alcohol dehydrogenase (ADH2). Carboxy-terminal deletions of the ADR1 protein (1,323 amino acids in length) were used to localize its functional regions. The transcriptional activation region was localized to the N-terminal 220 amino acids of ADR1 containing two DNA-binding zinc finger motifs. In addition to the N terminus, a large part of the ADR1 sequence was shown to be essential for complete activation of ADH2. Deletion of the putative phosphorylation region, defined by ADR1c mutations that overcome glucose repression, did not render ADH2 expression insensitive to glucose repression. Instead, this region (amino acids 220 through 253) was found to be required by ADR1 to bypass glucose repression. These results suggest that ADR1c mutations enhance ADR1 function, rather than block an interaction of the putative phosphorylation region with a repressor molecule. Furthermore, the protein kinase CCR1 was shown to affect ADH2 expression when the putative phosphorylation region was removed, indicating that CCR1 does not act solely through this region. A functional ADR1 gene was also found to be necessary for growth on glycerol-containing medium. The N-terminal 506 amino acids of ADR1 were required for this newly identified function, indicating that ADH2 activation and glycerol growth are controlled by separate regions of ADR1.


Asunto(s)
Proteínas de Unión al ADN , Proteínas Fúngicas/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/metabolismo , Secuencia de Aminoácidos , ADN de Hongos/metabolismo , Proteínas Fúngicas/genética , Regulación de la Expresión Génica/efectos de los fármacos , Glucosa/farmacología , Glicerol/metabolismo , Fosforilación , Conformación Proteica , Proteínas Quinasas/metabolismo , Saccharomyces cerevisiae/genética , Factores de Transcripción/genética
7.
Mol Cell Biol ; 6(11): 4026-30, 1986 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3540604

RESUMEN

The regulation of mRNA production for the yeast positive activator ADR1, a gene required for the expression of the glucose-repressible alcohol dehydrogenase (ADH II), was studied. ADR1 mRNA levels did not vary when yeasts were switched from glucose- to ethanol-containing medium, while ADH II expression increased 100-fold. The mRNA for the ADR1-5c allele, which augments ADH II expression 60-fold during glucose repression, was not present in greater abundance than ADR1 mRNA. Additionally, the ccr1-1 allele, which blocks ADH2 mRNA formation and partially suppresses the ADR1-5c phenotype, did not alter the levels of ADR1 mRNA. These results indicate that ADR1 is not transcriptionally controlled. To determine the character of the ADR1-5c mutation, the region containing the mutation was identified and sequenced. At base pair +683 a G-to-A transition was detected in the ADR1 coding sequence which would result in the substitution of a lysine residue for an arginine at amino acid 228. The location of the ADR1-5c mutation in the interior of the ADR1 coding sequences suggests that it enhances the activity of an extant but inactive ADR1 protein rather than increases the abundance of ADR1 by altered translation of its mRNA. The ADR1-5c mutation occurs in a region of the polypeptide corresponding to a cyclic AMP-dependent protein kinase phosphorylation recognition sequence. The potential role of reversible phosphorylation in the posttranslational regulation of ADR1 is discussed.


Asunto(s)
Genes Fúngicos , Genes Reguladores , Mutación , Procesamiento Proteico-Postraduccional , Saccharomyces cerevisiae/genética , Alcohol Deshidrogenasa/biosíntesis , Alcohol Deshidrogenasa/genética , Represión Enzimática , Genes , Glucosa/farmacología , Cinética , ARN Mensajero/genética , Saccharomyces cerevisiae/enzimología
8.
Mol Cell Biol ; 3(3): 360-70, 1983 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6341814

RESUMEN

The DNA segments containing the ADR1 gene and a mutant allele, ADR1-5c, have been isolated by complementation of function in Saccharomyces cerevisiae. The ADR1 gene is required for synthesis of the glucose-repressible alcohol dehydrogenase (ADHII) when S. cerevisiae cells are grown on a nonfermentable carbon source, whereas the ADR1-5c allele allows ADHII synthesis even during glucose repression. A plasmid pool consisting of yeast DNA fragments isolated from a strain carrying the ADR1-5c allele was used to transform a strain containing the adr1-1 allele, which prevents ADHII depression. Transformants were isolated which expressed ADHII during glucose repression. A plasmid isolated from one of these transformants was shown to carry the ADR1-5c allele by its ability to integrate at the chromosomal adr1-1 locus. The wild-type ADR1 gene was isolated by colony hybridization, using the cloned ADR1-5c gene as a probe. The ADR1-5c and ADR1 DNA segments were indistinguishable by restriction site mapping. A partial ADR1 phenotype could be conferred by a 1.9-kilobase region, but DNA outside of this region appeared to be necessary for normal activation of ADHII by the ADR1 gene.


Asunto(s)
Genes Reguladores , Saccharomyces cerevisiae/genética , Alcohol Deshidrogenasa , Oxidorreductasas de Alcohol/genética , Alelos , Clonación Molecular , Inducción Enzimática , Glucosa/farmacología , Mutación , Fenotipo , Plásmidos , Saccharomyces cerevisiae/enzimología
9.
Mol Cell Biol ; 15(7): 3487-95, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7791755

RESUMEN

The CCR4 protein from Saccharomyces cerevisiae is a component of a multisubunit complex that is required for the regulation of a number of genes in yeast cells. We report here the identification of a mouse protein (mCAF1 [mouse CCR4-associated factor 1]) which is capable of interacting with and binding to the yeast CCR4 protein. The mCAF1 protein was shown to have significant similarity to proteins from humans, Caenorhabditis elegans, Arabidopsis thaliana, and S. cerevisiae. The yeast gene (yCAF1) had been previously cloned as the POP2 gene, which is required for expression of several genes. Both yCAF1 (POP2) and the C. elegans homolog of CAF1 were shown to genetically interact with CCR4 in vivo, and yCAF1 (POP2) physically associated with CCR4. Disruption of the CAF1 (POP2) gene in yeast cells gave phenotypes and defects in transcription similar to those observed with disruptions of CCR4, including the ability to suppress spt10-enhanced ADH2 expression. In addition, yCAF1 (POP2) when fused to LexA was capable of activating transcription. mCAF1 could also activate transcription when fused to LexA and could functionally substitute for yCAF1 in allowing ADH2 expression in an spt10 mutant background. These data imply that CAF1 is a component of the CCR4 protein complex and that this complex has retained evolutionarily conserved functions important to eukaryotic transcription.


Asunto(s)
Proteínas de Arabidopsis , Proteínas Fúngicas/metabolismo , Regulación de la Expresión Génica , Proteínas , Ribonucleasas , Proteínas de Saccharomyces cerevisiae , Serina Endopeptidasas , Transaminasas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transcripción Genética , Secuencia de Aminoácidos , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Células Eucariotas/fisiología , Exorribonucleasas , Proteínas Fúngicas/genética , Leucina/genética , Ratones , Datos de Secuencia Molecular , Mutagénesis , Unión Proteica , Proteínas Recombinantes de Fusión/metabolismo , Secuencias Repetitivas de Ácidos Nucleicos , Proteínas Represoras , Homología de Secuencia de Aminoácido , Especificidad de la Especie , Relación Estructura-Actividad
10.
Mol Cell Biol ; 14(1): 629-40, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8264631

RESUMEN

The yeast transcriptional activator ADR1 is required for expression of the glucose-repressible alcohol dehydrogenase gene (ADH2), as well as genes involved in glycerol metabolism. The N-terminal half of the ADR1 protein was shown to contain three separate transactivation domains, including one (TADI) that encompasses the zinc finger DNA-binding domain. While TADII and TADIII were shown to be functionally redundant in activating ADH2 expression, deletion of only TADIII impaired ADR1 control of glycerol metabolism genes. None of these activation domains appeared to be carbon source regulated when separated from the ADH2 promoter context. Interspersed among these activation domains were two regions which, when removed, increased ADR1 activity; one was localized to the site of ADR1c mutations (residues 227 to 239) that allow glucose-insensitive ADH2 expression. The 227-to-239 region blocked ADR1 activity independently of the TAD present on ADR1, ADR1 DNA binding, and specific ADH2 promoter sequences. In addition, this region inhibited the function of a heterologous transcriptional activator. These results are consistent with the existence of an extragenic factor that binds the ADR1c region and represses ADR1 activity and suggest that other factors are responsible for aiding ADR1 in the carbon source regulation of ADH2.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Represoras/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/metabolismo , Alcohol Deshidrogenasa/genética , Secuencia de Bases , ADN de Hongos/genética , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Genes Fúngicos , Glicerol/metabolismo , Modelos Biológicos , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crecimiento & desarrollo , Eliminación de Secuencia , Transactivadores/genética , Transactivadores/metabolismo , Factores de Transcripción/química , Factores de Transcripción/genética , Dedos de Zinc/genética
11.
Mol Cell Biol ; 18(10): 5861-7, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9742103

RESUMEN

The yeast transcriptional activator ADR1, which is required for ADH2 and other genes' expression, contains four transactivation domains (TADs). While previous studies have shown that these TADs act through GCN5 and ADA2, and presumably TFIIB, other factors are likely to be involved in ADR1 function. In this study, we addressed the question of whether TFIID is also required for ADR1 action. In vitro binding studies indicated that TADI of ADR1 was able to retain TAFII90 from yeast extracts and TADII could retain TBP and TAFII130/145. TADIV, however, was capable of retaining multiple TAFIIs, suggesting that TADIV was binding TFIID from yeast whole-cell extracts. The ability of TADIV truncation derivatives to interact with TFIID correlated with their transcription activation potential in vivo. In addition, the ability of LexA-ADR1-TADIV to activate transcription in vivo was compromised by a mutation in TAFII130/145. ADR1 was found to associate in vivo with TFIID in that immunoprecipitation of either TAFII90 or TBP from yeast whole-cell extracts specifically coimmunoprecipitated ADR1. Most importantly, depletion of TAFII90 from yeast cells dramatically reduced ADH2 derepression. These results indicate that ADR1 physically associates with TFIID and that its ability to activate transcription requires an intact TFIID complex.


Asunto(s)
Proteínas de Ciclo Celular , Proteínas de Unión al ADN/metabolismo , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Factores Asociados con la Proteína de Unión a TATA , Factores de Transcripción TFII/metabolismo , Factores de Transcripción/metabolismo , Activación Transcripcional , Alcohol Deshidrogenasa/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Sitios de Unión , Proteínas de Unión al ADN/genética , Proteínas Fúngicas/genética , Pruebas de Precipitina , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Saccharomyces cerevisiae/metabolismo , Serina Endopeptidasas/genética , Serina Endopeptidasas/metabolismo , Proteína de Unión a TATA-Box , Factor de Transcripción TFIID , Factores de Transcripción/genética , Factores de Transcripción TFII/genética
12.
Mol Cell Biol ; 14(7): 4522-31, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8007957

RESUMEN

The yeast CCR4 protein is required for the expression of a number of genes involved in nonfermentative growth, including glucose-repressible ADH2, and is the only known suppressor of mutations in the SPT6 and SPT10 genes, two genes which are believed to be involved in chromatin maintenance. We show here that although CCR4 did not bind DNA under the conditions tested, it was able to activate transcription when fused to a heterologous DNA-binding domain. The transcriptional activation ability of CCR4, in contrast to that of many other activators, was glucose regulated. Two activation domains one of which was glucose responsive and encompassed a glutamine-proline-rich region similar to that found in other eukaryotic transcriptional factors were identified. The two transactivation regions, when separated from the leucine-rich repeat and the C terminus of CCR4, were unable to complement a defective ccr4 allele, suggesting that the leucine-rich repeat and the C terminus make contacts that link the activation regions to the proper gene context. Native immunoprecipitation of CCR4 revealed that CCR4 was complexed with at least four other proteins. The leucine-rich repeat of CCR4 was both necessary and sufficient for interaction with at least two of these factors. We propose that the leucine-rich repeat links CCR4 through its associated factors to its promoter context at ADH2 and other loci where it is required for proper transcriptional regulation.


Asunto(s)
Proteínas Fúngicas/metabolismo , Genes Fúngicos , Regiones Promotoras Genéticas , Ribonucleasas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Serina Endopeptidasas , Factores de Transcripción/metabolismo , Alcohol Deshidrogenasa/biosíntesis , Alcohol Deshidrogenasa/genética , Secuencia de Aminoácidos , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Clonación Molecular , Escherichia coli , Proteínas Fúngicas/biosíntesis , Leucina Zippers , Datos de Secuencia Molecular , Plásmidos , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/metabolismo , Secuencias Repetitivas de Ácidos Nucleicos , Mapeo Restrictivo , Regiones Terminadoras Genéticas , Factores de Transcripción/biosíntesis , beta-Galactosidasa/biosíntesis , beta-Galactosidasa/metabolismo
13.
Mol Cell Biol ; 12(4): 1507-14, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1549108

RESUMEN

Four ADR1c mutations that occur close to Ser-230 of the Saccharomyces cerevisiae transcriptional activator ADR1 and which greatly enhance the ability of ADR1 to activate ADH2 expression under glucose-repressed conditions have been shown to reduce or eliminate cyclic AMP-dependent protein kinase (cAPK) phosphorylation of Ser-230 in vitro. In addition, unregulated cAPK expression in vivo blocks ADH2 depression in an ADR1-dependent fashion in which ADR1c mutations display decreased sensitivity to unregulated cAPK activity. Taken together, these data have suggested that ADR1c mutations enhance ADR1 activity by blocking cAPK phosphorylation and inactivation of Ser-230. We have isolated and characterized an additional 17 ADR1c mutations, defining 10 different amino acid changes, that were located in the region defined by amino acids 227 through 239 of ADR1. Three observations, however, indicate that the ADR1c phenotype is not simply equivalent to a lack of cAPK phosphorylation. First, only some of these newly isolated ADR1c mutations affected the ability of yeast cAPK to phosphorylate corresponding synthetic peptides modeled on the 222 to 234 region of ADR1 in vitro. Second, we observed that strains lacking cAPK activity did not display enhanced ADH2 expression under glucose growth conditions. Third, when Ser-230 was mutated to a nonphosphorylatable residue, lack of cAPK activity led to a substantial increase in ADH2 expression under glucose-repressed conditions. Thus, while cAPK controls ADH2 expression and ADR1 is required for this control, cAPK acts by a mechanism that is independent of effects on ADR1 Ser-230. It was also observed that deletion of the ADR1c region resulted in an ADR1c phenotype. The ADR1c region is, therefore, involved in maintaining ADR1 in an inactive form. ADR1c mutations may block the binding of a repressor to ADR1 or alter the structure of ADR1 so that transcriptional activation regions become unmasked.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas Fúngicas/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Factores de Transcripción/genética , Transcripción Genética , Secuencia de Aminoácidos , Análisis Mutacional de ADN , Proteínas de Unión al ADN/genética , Modelos Genéticos , Datos de Secuencia Molecular , Péptidos/síntesis química , Péptidos/metabolismo , Fenotipo , Fosforilación , Proteínas Quinasas/metabolismo , Procesamiento Proteico-Postraduccional , Especificidad por Sustrato
14.
Mol Cell Biol ; 19(10): 6642-51, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10490603

RESUMEN

The CCR4-NOT complex (1 mDa in size), consisting of the proteins CCR4, CAF1, and NOT1 to NOT5, regulates gene expression both positively and negatively and is distinct from other large transcriptional complexes in Saccharomyces cerevisiae such as SNF/SWI, TFIID, SAGA, and RNA polymerase II holoenzyme. The physical and genetic interactions between the components of the CCR4-NOT complex were investigated in order to gain insight into how this complex affects the expression of diverse genes and processes. The CAF1 protein was found to be absolutely required for CCR4 association with the NOT proteins, and CCR4 and CAF1, in turn, physically interacted with NOT1 through its central amino acid region from positions 667 to 1152. The NOT3, NOT4, and NOT5 proteins had no significant effect on the association of CCR4, CAF1, and NOT1 with each other. In contrast, the NOT2, NOT4, and NOT5 interacted with the C-terminal region (residues 1490 to 2108) of NOT1 in which NOT2 and NOT5 physically associated in the absence of CAF1, NOT3, and NOT4. These and other data indicate that the physical ordering of these proteins in the complex is CCR4-CAF1-NOT1-(NOT2, NOT5), with NOT4 and NOT3 more peripheral to NOT2 and NOT5. The physical separation of CCR4 and CAF1 from other components of the CCR4-NOT complex correlated with genetic analysis indicating partially separate functions for these two groups of proteins. ccr4 or caf1 deletion suppressed the increased 3-aminotriazole resistance phenotype conferred by not mutations, resulted in opposite effects on gene expression as compared to several not mutations, and resulted in a number of synthetic phenotypes in combination with not mutations. These results define the CCR4-NOT complex as consisting of at least two physically and functionally separated groups of proteins.


Asunto(s)
Ribonucleasas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Factores de Transcripción/metabolismo , Sitios de Unión , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Mutación , Fenotipo , Unión Proteica , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Factores de Transcripción/genética
15.
Mol Cell Biol ; 19(2): 1056-67, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9891041

RESUMEN

Yeast contains at least two complex forms of RNA polymerase II (Pol II), one including the Srbps and a second biochemically distinct form defined by the presence of Paf1p and Cdc73p (X. Shi et al., Mol. Cell. Biol. 17:1160-1169, 1997). In this work we demonstrate that Ccr4p and Hpr1p are components of the Paf1p-Cdc73p-Pol II complex. We have found many synthetic genetic interactions between factors within the Paf1p-Cdc73p complex, including the lethality of paf1Delta ccr4Delta, paf1Delta hpr1Delta, ccr4Delta hpr1Delta, and ccr4Delta gal11Delta double mutants. In addition, paf1Delta and ccr4Delta are lethal in combination with srb5Delta, indicating that the factors within and between the two RNA polymerase II complexes have overlapping essential functions. We have used differential display to identify several genes whose expression is affected by mutations in components of the Paf1p-Cdc73p-Pol II complex. Additionally, as previously observed for hpr1Delta, deleting PAF1 or CDC73 leads to elevated recombination between direct repeats. The paf1Delta and ccr4Delta mutations, as well as gal11Delta, demonstrate sensitivity to cell wall-damaging agents, rescue of the temperature-sensitive phenotype by sorbitol, and reduced expression of genes involved in cell wall biosynthesis. This unusual combination of effects on recombination and cell wall integrity has also been observed for mutations in genes in the Pkc1p-Mpk1p kinase cascade. Consistent with a role for this novel form of RNA polymerase II in the Pkc1p-Mpk1p signaling pathway, we find that paf1Delta mpk1Delta and paf1Delta pkc1Delta double mutants do not demonstrate an enhanced phenotype relative to the single mutants. Our observation that the Mpk1p kinase is fully active in a paf1Delta strain indicates that the Paf1p-Cdc73p complex may function downstream of the Pkc1p-Mpk1p cascade to regulate the expression of a subset of yeast genes.


Asunto(s)
Proteínas Fúngicas/metabolismo , Proteínas Nucleares/metabolismo , Proteína Quinasa C/metabolismo , ARN Polimerasa II/metabolismo , Ribonucleasas , Proteínas de Saccharomyces cerevisiae , Factores de Transcripción/metabolismo , Secuencia de Bases , Pared Celular/metabolismo , Cartilla de ADN/genética , Proteínas Fúngicas/genética , Eliminación de Gen , Genes Fúngicos , Sustancias Macromoleculares , Modelos Biológicos , Mutación , Proteínas Nucleares/genética , Fenotipo , Recombinación Genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transducción de Señal , Factores de Transcripción/genética , Transcripción Genética
16.
Mol Cell Biol ; 12(4): 1663-73, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1549119

RESUMEN

The rate of ADH2 transcription increases dramatically when Saccharomyces cerevisiae cells are shifted from glucose to ethanol growth conditions. Since ADH2 expression under glucose growth conditions is strictly dependent on the dosage of the transcriptional activator ADR1, we investigated the possibility that regulation of the rate of ADR1 protein synthesis plays a role in controlling ADR1 activation of ADH2 transcription. We found that the rate of ADR1 protein synthesis increased 10- to 16-fold within 40 to 60 min after glucose depletion, coterminous with initiation of ADH2 transcription. Changes in ADR1 mRNA levels contributed only a twofold effect on ADR1 protein synthetic differences. The 510-nt untranslated ADR1 mRNA leader sequence was found to have no involvement in regulating the rate of ADR1 protein synthesis. In contrast, sequences internal to ADR1 coding region were determined to be necessary for controlling ADR1 translation. The ADR1c mutations which enhance ADR1 activity under glucose growth conditions did not affect ADR1 protein translation. ADR1 was also shown to be multiply phosphorylated in vivo under both ethanol and glucose growth conditions. Our results indicate that derepression of ADH2 occurs through multiple mechanisms involving the ADR1 regulatory protein.


Asunto(s)
Alcohol Deshidrogenasa/metabolismo , Proteínas de Unión al ADN/metabolismo , Represión Enzimática , Proteínas Fúngicas/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/metabolismo , Sitios de Unión , Proteínas de Unión al ADN/genética , Etanol/metabolismo , Proteínas Fúngicas/química , Regulación Fúngica de la Expresión Génica , Glucosa/metabolismo , Mutación , Fosforilación , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Factores de Tiempo
17.
Mol Cell Biol ; 18(4): 2100-7, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9528782

RESUMEN

The DBF2 gene of the budding yeast Saccharomyces cerevisiae encodes a cell cycle-regulated protein kinase that plays an important role in the telophase/G1 transition. As a component of the multisubunit CCR4 transcriptional complex, DBF2 is also involved in the regulation of gene expression. We have found that MOB1, an essential protein required for a late mitotic event in the cell cycle, genetically and physically interacts with DBF2. DBF2 binds MOB1 in vivo and can bind it in vitro in the absence of other yeast proteins. We found that the expression of MOB1 is also cell cycle regulated, its expression peaking slightly before that of DBF2 at the G2/M boundary. While overexpression of DBF2 suppressed phenotypes associated with mob1 temperature-sensitive alleles, it could not suppress a mob1 deletion. In contrast, overexpression of MOB1 suppressed phenotypes associated with a dbf2-deleted strain and suppressed the lethality associated with a dbf2 dbf20 double deletion. A mob1 temperature-sensitive allele with a dbf2 disruption was also found to be synthetically lethal. These results are consistent with DBF2 acting through MOB1 and aiding in its function. Moreover, the ability of temperature-sensitive mutated versions of the MOB1 protein to interact with DBF2 was severely reduced, confirming that binding of DBF2 to MOB1 is required for a late mitotic event. While MOB1 and DBF2 were found to be capable of physically associating in a complex that did not include CCR4, MOB1 did interact with other components of the CCR4 transcriptional complex. We discuss models concerning the role of DBF2 and MOB1 in controlling the telophase/G1 transition.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Ciclo Celular , Proteínas Fúngicas/metabolismo , Fosfoproteínas/metabolismo , Proteínas Quinasas/metabolismo , Proteínas de Saccharomyces cerevisiae , Alelos , Proteínas Bacterianas/metabolismo , Proteínas de Ciclo Celular/genética , Mitosis , Fenotipo , Fosfoproteínas/genética , Unión Proteica , Proteínas Serina-Treonina Quinasas , Saccharomyces cerevisiae , Serina Endopeptidasas/metabolismo
18.
J Clin Transl Res ; 2(2): 63-69, 2016 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-30873463

RESUMEN

BACKGROUND AND AIM: Rapid weight loss (RWL) is extensively practiced by combat sports athletes, including Mixed Martial Arts (MMA), but its effects on performance are not well established with different magnitudes of RWL, including those higher than 5% of total body weight. The aim of the present study was to follow MMA athletes during RWL with subsequent weight regain to evaluate the responses of isometric strength, power, cognition and salivary nitrite ( NO 2 - ) content. METHODS: Two professional male MMA fighters, same age, competing in the same weight category underwent two magnitudes of RWL before a simulated competition period. Anthropometric measures, records of nutritional status, training, voluntary dehydration strategies, salivary samples, cognition response, isometric strength and muscular power were obtained: (I) 7 days before combat, (II) at the weigh-in moment, and (III) in the combat day. RESULTS AND CONCLUSIONS: Athlete 1 lost 7.2 kg (9.1% of total bodyweight) and Athlete 2 lost 4.0 kg (5.3% of total bodyweight). Athlete 1 had a lower and misbalanced caloric ingestion (708 ± 428 kcal), ingested 6 L of water during the first 5 days of RWL, underwent 2 days of fasting, water and sodium restriction before weigh-in. Athlete 2 was supervised by a nutritionist, had a balanced diet (1600 ± 0 kcal), ingested 2 L of water during the first 6 days of RWL, underwent only 1 day of fasting and water restriction, and did not restrict sodium. As expected, there was a negative effect of RWL in the evaluated parameters at the weigh-in moment, while in the combat day, salivary NO 2 - ) content. METHODS: Two professional male MMA fighters, same age, competing in the same weight category underwent two magnitudes of RWL before a simulated competition period. Anthropometric measures, records of nutritional status, training, voluntary dehydration strategies, salivary samples, cognition response, isometric strength and muscular power were obtained: (I) 7 days before combat, (II) at the weigh-in moment, and (III) in the combat day. RESULTS AND CONCLUSIONS: Athlete 1 lost 7.2 kg (9.1% of total bodyweight) and Athlete 2 lost 4.0 kg (5.3% of total bodyweight). Athlete 1 had a lower and misbalanced caloric ingestion (708 ± 428 kcal), ingested 6 L of water during the first 5 days of RWL, underwent 2 days of fasting, water and sodium restriction before weigh-in. Athlete 2 was supervised by a nutritionist, had a balanced diet (1600 ± 0 kcal), ingested 2 L of water during the first 6 days of RWL, underwent only 1 day of fasting and water restriction, and did not restrict sodium. As expected, there was a negative effect of RWL in the evaluated parameters at the weigh-in moment, while in the combat day, salivary NO 2 - was not completely reestablished at baseline levels (decreased by 35.9% in Athlete 1 and, 25.2% in Athlete 2, as compared with 7 days before). The athlete who underwent a lower weight loss (5.3%) presented better recovery of cognition and upper limbs power on the combat day as compared with the athlete who lost 9.1% of body weight. Although we cannot precisely conclude, this case report led us to believe that the recovery period between weigh-in and competition may be insufficient for total reestablishment of salivary NO 2 - after RWL, and higher amounts of RWLhave negative impacts on average power and cognition when compared with lower RWL.Relevance for patients: Scientific aspects related with performance in MMA athletes brought to light the absence of studies investigating the recovery of isometric strength, power, cognition and salivary NO 2 - during RWL with subsequent weight regain. This study revealed that athletes from the same categories can adopt different magnitudes of weight loss, and that this procedure impacts several important measures, for example, the reduction of salivary NO 2 - is associated with the lower O2 transport capacity, decreasing muscle performance.

19.
Front Physiol ; 7: 260, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27445850

RESUMEN

The aim of this study was to investigate the effects of two consecutive Crossfit® training sessions (24 h apart) designed to enhance work-capacity that involved both cardiovascular and muscular exercises on cytokines, muscle power, blood lactate and glucose. Nine male members of the CrossFit® community (age 26.7 ± 6.6 years; body mass 78.8 ± 13.2 kg; body fat 13.5 ± 6.2%; training experience 2.5 ± 1.2 years) completed two experimental protocols (24 h apart): (1) strength and power exercises, (2) gymnastic movements, and (3) metabolic conditioning as follows: 10 min of as many rounds as possible (AMRAP) of 30 double-unders and 15 power snatches (34 kg). The same sequence as repeated on session 2 with the following metabolic conditioning: 12 min AMRAP of: row 250 m and 25 target burpees. Serum interleukin-6 (IL-6), IL-10, and osteoprotegerin were measured before, immediately post and 24 h after workout of the day (WOD) 1, immediately post, 24 and 48 h after WOD 2. Peak and mean power were obtained for each repetition (back squat with 50% of 1 repetition maximum) using a linear position transducer measured before, immediately post and 24 h after WOD 1, immediately post and 24 h after WOD 2. Blood lactate and glucose were measured pre and immediately post WOD 1 and 2. Although both sessions of exercise elicited an significant increase in blood lactate (1.20 ± 0.41 to 11.84 ± 1.34 vs. 0.94 ± 0.34 to 9.05 ± 2.56 mmol/l) and glucose concentration (81.59 ± 10.27 to 114.99 ± 12.52 vs. 69.47 ± 6.97 to 89.95 ± 19.26 mg/dL), WOD 1 induced a significantly greater increase than WOD 2 (p ≤ 0.05). The training sessions elicited significant changes (p ≤ 0.05) in IL-6, IL-10 and osteoprotegerin concentration over time. IL-6 displayed an increase immediately after training WOD 1 [197 ± 109%] (p = 0.009) and 2 [99 ± 58%] (p = 0.045). IL-10 displayed an increase immediately after only WOD 1 [44 ± 52%] (p = 0.046), and decreased 24 and 48 h following WOD 2 (~40%; p = 0.018) as compared to pre-exercise values. Osteoprotegerin displayed a decrease 48 h following WOD 2 (~25%; p = 0.018) as compared with pre intervention. In conclusion, two consecutive Crossfit® training sessions increase pro/anti-inflammatory cytokines with no interference on muscle performance in the recovery period.

20.
J Mol Biol ; 314(4): 683-94, 2001 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-11733989

RESUMEN

The CCR4-NOT complex is an evolutionarily conserved, transcriptional regulatory complex that is involved in controlling mRNA initiation, elongation and degradation. The CCR4-NOT proteins from Saccharomyces cerevisiae exist in two complexes, 1.9x10(6) Da and 1.0x10(6) Da (1.0 MDa) in size, and individual components of these complexes display such disparate functions as binding to and restricting TFIID functions, contacting SAGA and contributing to mRNA deadenylation. As a first step in characterizing the functional roles of the 1.0 MDa complex, we have purified it to near homogeneity. Mass spectrometric analysis was subsequently used to identify all the components of the complex. The 1.0 MDa complex was found to contain CCR4, CAF1, NOT1-5 and two new proteins, CAF40 and CAF130. CAF130 and CAF40 are two unique yeast proteins, with CAF40 displaying extensive homology to proteins from other eukaryotes. Immunoprecipitation and gel filtration experiments confirmed that CAF130 and CAF40 are components of both of the 1.9 MDa and 1.0 MDa CCR4-NOT complexes. Biochemical analysis indicated that the CAF40 and CAF130 proteins bind to the NOT1 protein and exist in a location separate from the two other subsets of proteins in the complex: the CCR4 and CAF1 proteins, and the NOT2, NOT4 and NOT5 proteins. Moreover, CAF40 was able to interact with human NOT1, suggesting that human CAF40 would also be a component of the recently identified human CCR4-NOT complex. Analysis of caf40 and caf130 deletions indicated that they elicited phenotypes shared by defects in other CCR4-NOT genes. The distinct location of CAF40 and CAF130 and the evolutionary conservation of CAF40 implicate them in novel roles in the function of the CCR4-NOT complex.


Asunto(s)
Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Proteínas , Ribonucleasas , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/química , Factores de Transcripción/química , Factores de Transcripción/metabolismo , Sitios de Unión , Western Blotting , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/aislamiento & purificación , Cromatografía en Gel , Evolución Molecular , Proteínas Fúngicas/genética , Proteínas Fúngicas/aislamiento & purificación , Eliminación de Gen , Humanos , Sustancias Macromoleculares , Espectrometría de Masas , Modelos Biológicos , Peso Molecular , Fenotipo , Pruebas de Precipitina , Unión Proteica , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/aislamiento & purificación , Homología de Secuencia , Factores de Transcripción/genética , Factores de Transcripción/aislamiento & purificación , Técnicas del Sistema de Dos Híbridos
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