Search results for "CONTACT"

p38α MAPK is required for contact inhibition

2005

Proliferation of nontransformed cells is regulated by cell-cell contacts, which are referred to as contact-inhibition. Despite its generally accepted importance for cell cycle control, knowledge about the intracellular signalling pathways involved in contact inhibition is scarce. In the present work we show that p38alpha mitogen-activated protein kinase (MAPK) is involved in the growth-inhibitory signalling cascade of contact inhibition in fibroblasts. p38alpha activity is increased in confluent cultures of human fibroblasts compared to proliferating cultures. Time course studies show a sustained activation of p38alpha in response to cell-cell contacts in contrast to a transient activation …

Regulation of ERK1/2 activity upon contact inhibition in fibroblasts.

2011

Contact inhibition is a crucial mechanism regulating proliferation in vitro and in vivo. Despite its generally accepted importance for maintaining tissue homeostasis knowledge about the underlying molecular mechanisms of contact inhibition is still scarce. Since the MAPK ERK1/2 plays a pivotal role in the control of proliferation, we investigated regulation of ERK1/2 phosphorylation which is downregulated in confluent NIH3T3 cultures. We found a decrease in upstream signaling including phosphorylation of the growth factor receptor adaptor protein ShcA and the MAPK kinase MEK1/2 in confluent compared to exponentially growing cultures whereas involvement of ERK1/2 phosphatases in ERK1/2 inact…

Involvement of the transcription factor FoxM1 in contact inhibition

2012

Contact inhibition is a crucial mechanism regulating proliferation in vitro and in vivo. Although it is generally accepted that contact inhibition plays a pivotal role in maintaining tissue homeostasis, the molecular mechanisms of contact inhibition are still not fully understood. FoxM1 is known as a proliferation-associated transcription factor and is upregulated in many cancer types. Vice versa, anti-proliferative signals, such as TGF-β and differentiation signals decrease FoxM1 expression. Here we investigated the role of FoxM1 in contact inhibition in fibroblasts. We show that protein expression of FoxM1 is severely and rapidly downregulated upon contact inhibition, probably by inhibiti…

The Late Endosomal Adaptor Molecule p14 (LAMTOR2) Regulates TGFβ1-Mediated Homeostasis of Langerhans Cells

2014

Langerhans cells (LCs), a sub-population of dendritic cells (DCs) in the skin, participate in the regulation of immunity and peripheral tolerance. The adaptor molecule p14 is part of the late endosomal/lysosomal adaptor and mitogen-activated protein kinase and mammalian target of rapamycin (mTOR) activator/regulator (LAMTOR) complex, which mediates the activation of lysosome-associated extracellular signaling regulated kinase (ERK) and the mTOR cascade. In previous work, we demonstrated that CD11c-specific deficiency of p14 disrupts LC homeostasis by affecting the LAMTOR-mediated ERK and mTOR signaling. In this study, we extended our analysis on p14 deficiency specifically in LCs. Langerin-…

Nuclear Magnetic Moments ofBi205,207,209Isotopes—Hyperfine Structure of the 15-dayBi2053067-Å Line

1975

CNTN6 mutations are risk factors for abnormal auditory sensory perception in autism spectrum disorders

2017

International audience; Contactin genes CNTN5 and CNTN6 code for neuronal cell adhesion molecules that promote neurite outgrowth in sensory-motor neuronal pathways. Mutations of CNTN5 and CNTN6 have previously been reported in individuals with autism spectrum disorders (ASDs), but very little is known on their prevalence and clinical impact. In this study, we identified CNTN5 and CNTN6 deleterious variants in individuals with ASD. Among the carriers, a girl with ASD and attention-deficit/hyperactivity disorder was carrying five copies of CNTN5. For CNTN6, both deletions (6/1534 ASD vs 1/8936 controls; P=0.00006) and private coding sequence variants (18/501 ASD vs 535/33480 controls; P=0.000…

Hormonal changes of intimate partner violence perpetrators in response to brief social contact with women

2022

This study investigated whether men with a history of real-life aggressive, dominant behavior show increases in testosterone and cortisol levels after brief social contact with women. Furthermore, we tested the prediction that such changes in hormones would be larger than those observed previously in young male students. Sixty-seven male participants convicted of intimate partner violence (IPV) either had brief social contact with a female confederate (experimental condition) or a male confederate (control condition). We also performed meta-analyses to investigate whether IPV perpetrators' hormonal responses were larger than the typical responses of young male students in prior studies. All…

Obstacles to intergroup contact: When outgroup partner's anxiety meets perceived ethnic discrimination

2013

Emerging research suggests that outgroup partner's anxiety can disrupt intergroup rapport-building. This study extends previous findings by investigating the interactive effects of anticipated outgroup partner's anxiety and perceived ethnic discrimination on self-anxiety and intergroup contact avoidance. A sample of immigrant adolescents belonging to different ethnic minorities in Italy (N = 118) was considered. Results showed that when participants expected to interact with an anxious outgroup (Italian) versus in-group partner, self-anxiety increased and, as a consequence, their intentions to avoid future encounters. However, these effects were observed only for participants with higher (v…

Contact sensitivity to oxazolone in the chicken: evidence for Arthus type hypersensitivity of the cutaneous reaction.

1992

Cutaneous hypersensitivity reaction can be induced in chickens by skin painting with oxazolone, 33 mg/Kg of body weight (KBW). The B cell contribution to the generation of the cutaneous reaction has been a matter of controversy. In an attempt to characterize this reaction we placed special interest on the possibility that the nature of this reaction could be Arthus type hypersensitivity. From the kinetics study on the cutaneous hypersensitivity after challenge with oxazolonated egg-albumin (EA-OX) it was excluded that the nature of this reaction could be delayed type hypersensitivity. Immune sera transfer experiments demonstrated that the cutaneous reaction was antibody dependent. Serum ant…

Increased Level of Intracellular MHC Class II Molecules in Murine Langerhans Cells Following In Vivo and In Vitro Administration of Contact Allergens

1992

Treatment of murine Langerhans cells (LC) with contact allergens results in increased internalization of cell membrane constituents and therefore in depressed cell-surface expression of major histocompatibility complex (MHC) class II molecules during the first hours after haptenization. In this presentation we show that this downregulation of cell-surface-expressed Ia-antigens is accompanied by an augmentation of the intracellular pool of MHC class II molecules. Rat MoAb 2G9 was developed, which recognizes IA and IE molecules of the d-haplotype. This MoAb competes with the murine MoAb MK-D6 for binding sites to IAd-molecules. After blocking the cell-surface-expressed molecules with 2G9 and …