Abstract:
:Activating ras point mutations are frequently found in skeletal muscle tumors such as rhabdomyosarcomas. In this study we investigated the impact of two different H-ras mutants in skeletal muscle differentiation: RasV12, a constitutively active form, and RasV12C40, a mutant deficient in Raf1 activation. Stably transfected C2C12-RasV12 myoblasts actively proliferated as indicated by the sustained expression of proliferating cell nuclear antigen and retinoblastoma at the hyperphosphorylated state and failed to express differentiation markers. This differentiation-defective phenotype was a consequence of the chronic p44/p42MAPK phosphorylation and the inability of the cells to activate AKT. Moreover, we observed that p44/p42MAPK activation in C2C12-RasV12 myoblasts phosphorylated the ETS-like transcription factor (ELK) 1, which translocates to the nuclei and seemed to be involved in maintaining myoblast proliferation. C2C12-RasV12C40 myoblasts cultured in low serum repressed phosphorylation of p44/p42MAPK and ELK1, resulting in cell cycle arrest and myogenic differentiation. Under this condition, activation of AKT, p70S6K, and p38MAPK was produced, leading to formation of myotubes in 3 d, 1 d earlier than in control C2C12-AU5 cells. Moreover, the expression of muscle-specific proteins, mainly the terminal differentiation markers caveolin-3 and myosin heavy chain, also occurred 1 d earlier than in control cells. Furthermore, AKT activation produced phosphorylation of Forkhead box O that led to nuclear exclusion and inactivation, allowing myogenesis. In addition, we found an induction of nuclear factor-kappaB activity in the nucleus in C2C12-RasV12C40 myotubes attributed to p38MAPK activation. Accordingly, muscle differentiation is associated with a pattern of transcription factors that involves nuclear exclusion ELK1 and Forkhead box O and the increase in nuclear factor-kappaB DNA binding.
journal_name
Endocrinologyjournal_title
Endocrinologyauthors
De Alvaro C,Nieto-Vazquez I,Rojas JM,Lorenzo Mdoi
10.1210/en.2007-0657subject
Has Abstractpub_date
2008-02-01 00:00:00pages
793-801issue
2eissn
0013-7227issn
1945-7170pii
en.2007-0657journal_volume
149pub_type
杂志文章相关文献
ENDOCRINOLOGY文献大全abstract::Removal of fetuses at day 14 of gestation (Ftx14) in the pregnant rat leads to a marked suppression of serum levels of rat placental lactogen (rPL-II). One might attribute this to compromised placental growth in the absence of a fetus. However, if ovariectomy and fetectomy (Ftx14 Ovx14) are carried out at the same tim...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-114-1-22
更新日期:1984-01-01 00:00:00
abstract::The levels of the GnRH receptor (GnRHR) and its messenger RNA depend on the pattern of administration of GnRH. In this study, internal deletion mutants in a luciferase reporter gene vector (GnRHR-pXP2) containing a 1226-bp promoter fragment of mouse GnRHR gene were used to examine the regulation of GnRHR gene transcri...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.140.8.6945
更新日期:1999-08-01 00:00:00
abstract::GnRH regulates the secretion of LH and FSH, which stimulate the secretion of testicular hormones. Acting in a reciprocal fashion, these hormones, including testosterone and inhibin, exert a negative feedback effect on GnRH and gonadotropin secretion. Endogenous opioid peptides (EOPs) have been implicated to play a rol...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-124-4-1697
更新日期:1989-04-01 00:00:00
abstract::Prolonged exposure of many types of cells to drugs or hormones that inhibit the activity of the enzyme adenylate cyclase, such as narcotics and alpha 2-adrenergic agonists, leads to enhanced accumulation of cAMP upon removal of the inhibitory drug. We have found previously that chronic infusion of the adenosine A1 rec...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-124-5-2434
更新日期:1989-05-01 00:00:00
abstract::We studied the effects of the guanine nucleotide-binding regulatory protein (Gs) from human erythrocytes on PTH-responsive adenylate cyclase from partially purified membranes of canine renal cortex (CRC). Extracts of erythrocyte membranes, containing soluble Gs, was obtained by treatment with a detergent (Lubrol PX). ...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-115-4-1386
更新日期:1984-10-01 00:00:00
abstract::Concern that some chemicals in our environment may affect human health by disrupting normal endocrine function has prompted research on interactions of environmental contaminants with steroid hormone receptors. We compared the activity of 2,2-bis-(p-hydroxyphenyl)-1,1,1-trichloroethane (HPTE), an estrogenic metabolite...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.140.12.7191
更新日期:1999-12-01 00:00:00
abstract::Orexins/hypocretins heavily innervate the posterior division of the paraventricular nucleus of the thalamus (pPVT), which expresses both orexin receptor types. The pPVT is important for adaptations to repeated stress, particularly the ability to facilitate to novel stress after repeated stress exposure. Here, we exami...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2011-1652
更新日期:2011-12-01 00:00:00
abstract::Kisspeptin neurons play an essential role in the regulation of fertility through direct regulation of the GnRH neurons. However, the relative contributions of the two functionally distinct kisspeptin neuron subpopulations to this critical regulation are not fully understood. Here we analyzed the specific projection pa...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2015-1131
更新日期:2015-07-01 00:00:00
abstract::The present study was designed to evaluate the relative contribution of endogenous excitatory amino acids to the control of the estradiol-induced LH surge using specific blockers for N-methyl-D-aspartic acid (NMDA) and non-NMDA receptor types. Adult female rats ovariectomized for 2-3 weeks were implanted with third ve...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-126-3-1771
更新日期:1990-03-01 00:00:00
abstract::CRF dose-dependently enhanced corticosterone (B) secretion by rat adrenal slices including both cortex and medulla. Conversely, CRF did not exert any B response by fragments of adrenocortical autotransplants, which are completely deprived of chromaffin tissue. However, autotransplant quarters exhibited a dose-dependen...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.131.1.1319330
更新日期:1992-07-01 00:00:00
abstract::Previously, we have demonstrated an inhibitory effect of oxytocin (OXT) on progesterone (P) and androstenedione (A) release of porcine luteal cell cultures. The present study examines whether OXT modulates P, A, or estradiol (E2) release of so-called small luteal cells (SLC) or of granulosa-derived large luteal cells ...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-126-5-2343
更新日期:1990-05-01 00:00:00
abstract::Two different types of corticoid receptor molecules bind circulating corticosterone in brain: mineralocorticoid receptors (MR) and glucocorticoid receptors. MR exhibit the highest affinity for the endogenous glucocorticoid in the rat, corticosterone. During development, low corticosterone levels influence neurogenesis...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.139.7.6095
更新日期:1998-07-01 00:00:00
abstract::Exposure of FRTL-5 cells to iodide (I-) in excess of 3 microM suppresses the concentrative uptake of I-. The depression of I- uptake measured at the steady state is due to decrease in the rate of I- influx and not to an effect on I- efflux. Exposure to NaI is associated with decreased T4 secretion and also depressed N...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-118-6-2477
更新日期:1986-06-01 00:00:00
abstract::Stearoyl-CoA desaturase-1 (SCD-1) plays a pivotal role in an increase of triglyceride by an excess of dietary carbohydrate intake. Dietary carbohydrates increase SCD-1 gene expression in liver by sterol response element binding protein (SREBP)-1c-dependent and SREBP-1c -independent pathways. Previous report demonstrat...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2012-1559
更新日期:2013-01-01 00:00:00
abstract::The calcium-dependent class of cell adhesion molecules known as cadherins mediate homotypic cell interactions in most epithelia. We have now investigated the expression and distribution of cadherins and cadherin-associated molecules in the developing and maturing rat testis. E-Cadherin was not detected in the seminife...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.134.2.7507830
更新日期:1994-02-01 00:00:00
abstract::Sertoli cells regulate differentiation and development of the testis and are essential for maintaining adult testis function. To model the effects of dysregulating Sertoli cell number during development or aging, we have used acute diphtheria toxin-mediated cell ablation to reduce Sertoli cell population size. Results...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2017-00196
更新日期:2017-09-01 00:00:00
abstract::Aldo-keto-reductase 1B7/mouse vas deferens protein (AKR1B7/MVDP) is expressed in rodent steroidogenic glands and in the mouse vas deferens. In steroidogenic organs, AKR1B7/MVDP scavenges isocaproaldehyde produced from the cholesterol side-chain cleavage reaction. Akr1b7/mvdp is responsive to ACTH in adrenals and to an...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2002-220825
更新日期:2003-05-01 00:00:00
abstract::Type 3 deiodinase (D3), the physiologic inactivator of thyroid hormones, is induced during tissue injury and regeneration. This has led to the hypotheses that D3 impacts injury tolerance by reducing local T3 signaling and contributes to the fall in serum triiodothyronine (T3) observed in up to 75% of sick patients (te...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2013-2028
更新日期:2014-10-01 00:00:00
abstract::It has previously only been possible to assess osteoclastic bone resorption in intact bone, where other cell types may modify or mediate osteoclastic responses to environmental agents. We have recently developed techniques which enable us to measure bone resorption by osteoclasts extracted from bone and have used thes...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-116-1-234
更新日期:1985-01-01 00:00:00
abstract::The effects of estrogen on the synthesis of pituitary PRL mRNA and PRL and the release of PRL into plasma were investigated in male and female normal and hypogonadal (hpg) mice. Because the hpg mouse is totally deficient in hypothalamic GnRH, it provides an excellent model for investigating the effects of estrogen and...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-119-6-2422
更新日期:1986-12-01 00:00:00
abstract::Leptin, a pleiotropic adipokine, is a central regulator of appetite and weight and a key immunomodulatory protein. Although inborn leptin deficiency causes weight gain, it is unclear whether induced leptin deficiency in adult wild-type animals would be orexigenic. Previous work with a potent competitive leptin antagon...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2008-1706
更新日期:2009-07-01 00:00:00
abstract::In this study we tested the hypothesis that receptor-mediated transport of urocortin across the blood-brain barrier (BBB) undergoes developmental changes. Urocortin is a peptide produced by both selective brain regions and peripheral organs, and it is involved in feeding, memory, mood, cardiovascular functions, and im...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2009-1039
更新日期:2010-03-01 00:00:00
abstract::The evolution of the IGF binding protein (IGFBP) gene family has been difficult to resolve. Both chromosomal and serial duplications have been suggested as mechanisms for the expansion of this gene family. We have identified and annotated IGFBP sequences from a wide selection of vertebrate species as well as Branchios...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2011-0047
更新日期:2011-06-01 00:00:00
abstract::Two corticotropin-releasing factor 2 receptor (CRF2R)-selective peptides have been recently described, urocortin II (also known as stresscopin-related peptide) and urocortin III (stresscopin). We have used urocortin II to evaluate the effects of activation of the CRF2R on skeletal muscle-related physiological processe...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2003-0271
更新日期:2003-11-01 00:00:00
abstract::The ability of cells to directly respond to glucocorticoids and aldosterone is a function of GR and MR expression, and coexpression of 11beta-hydroxysteroid dehydrogenases (11betaHSDs), which convert glucocorticoids and their 11-ketometabolites into either receptor inactive or active derivatives. The aim of the presen...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.143.1.8583
更新日期:2002-01-01 00:00:00
abstract::Hypothalamic inflammation and gliosis are proposed to participate in the pathogenesis of high-fat diet-induced obesity. Because other factors and nutrients also induce weight gain and adiposity, we analyzed the inflammatory and glial responses to a sucrose (S)-enriched diet. Neonatal overnutrition (NON) exacerbates we...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2012-2196
更新日期:2013-07-01 00:00:00
abstract::In amphibians, the secretion of alpha-MSH by melanotrope cells is stimulated by TRH and inhibited by NPY. We have previously shown that NPY abrogates the stimulatory effect of TRH on alpha-MSH secretion. The aim of the present study was to characterize the receptor subtypes mediating the action of NPY and to investiga...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.143.5.8761
更新日期:2002-05-01 00:00:00
abstract::With the use of rabbit anti-LH-RH serum, a system of delicate nerve fibers and terminals which contain immunoreactive LH-RH can be demonstrated in the median eminence of the rat, corresponding exactly to the tubero-infundibular tract as described earlier with the aid of classical neurophistological methods. The delica...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-96-1-135
更新日期:1975-01-01 00:00:00
abstract::The osteoclast is known to be derived from the hemopoietic stem cell, but its lineage and the mechanisms by which its differentiation is regulated are largely unknown. There is evidence that osteoclastic differentiation is induced through a contact-dependent interaction between bone marrow stromal cells and hemopoieti...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-128-1-259
更新日期:1991-01-01 00:00:00
abstract::Interleukin-1 (IL-1) greatly induces osteoclast formation and stimulates bone resorption of mouse calvaria in culture. In the presence of soluble IL-6 receptor (sIL-6R), IL-6 similarly induces osteoclast formation, but the potency of IL-6 in inducing bone resorption in organ culture is weaker than that of IL-1. To stu...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.139.3.5818
更新日期:1998-03-01 00:00:00