scholarly journals Emergent memory in cell signaling: Persistent adaptive dynamics in cascades can arise from the diversity of relaxation time-scales

2018 ◽  
Author(s):  
Tanmay Mitra ◽  
Shakti N. Menon ◽  
Sitabhra Sinha
Keyword(s):  
Cell Fate ◽  
Short Term Memory ◽  
Adaptive Dynamics ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Eukaryotic Cells ◽  
Adaptive Responses ◽  
Relaxation Rates ◽  
Cell Fate Decisions ◽  
Mitogen Activated Protein

The mitogen-activated protein kinase (MAPK) signaling cascade, an evolutionarily conserved motif present in all eukaryotic cells, is involved in coordinating critical cell-fate decisions, regulating protein synthesis, and mediating learning and memory. While the steady-state behavior of the pathway stimulated by a time-invariant signal is relatively well-understood, we show using a computational model that it exhibits a rich repertoire of transient adaptive responses to changes in stimuli. When the signal is switched on, the response is characterized by long-lived modulations in frequency as well as amplitude. On withdrawing the stimulus, the activity decays over timescales much longer than that of phosphorylation-dephosphorylation processes, exhibiting reverberations characterized by repeated spiking in the activated MAPK concentration. The long-term persistence of such post-stimulus activity suggests that the cascade retains memory of the signal for a significant duration following its removal, even in the absence of any explicit feedback or cross-talk with other pathways. We find that the molecular mechanism underlying this behavior is related to the existence of distinct relaxation rates for the different cascade components. This results in the imbalance of fluxes between different layers of the cascade, with the repeated reuse of activated kinases as enzymes when they are released from sequestration in complexes leading to one or more spike events following the removal of the stimulus. The persistent adaptive response reported here, indicative of a cellular “short-term” memory, suggests that this ubiquitous signaling pathway plays an even more central role in information processing by eukaryotic cells.

scholarly journals Graded Mitogen-Activated Protein Kinase Activity Precedes Switch-Like c-Fos Induction in Mammalian Cells

2005 ◽  
Vol 25 (11) ◽  
pp. 4676-4682 ◽  
Author(s):  
Jeffrey P. MacKeigan ◽  
Leon O. Murphy ◽  
Christopher A. Dimitri ◽  
John Blenis
Keyword(s):  
Protein Kinase ◽  
Cell Fate ◽  
Oocyte Maturation ◽  
Mammalian Cells ◽  
Mapk Pathway ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Cell Fate Decisions ◽  
Graded Response ◽  
Mitogen Activated Protein

ABSTRACT The mitogen-activated protein kinase (MAPK) pathway is an evolutionarily conserved signaling module that controls important cell fate decisions in a variety of physiological contexts. During Xenopus oocyte maturation, the MAPK cascade converts an increasing progesterone stimulus into a switch-like, all-or-nothing response. While the importance of such switch-like behavior is widely discussed in the literature, it is not known whether the MAPK pathway in mammalian cells exhibits a switch-like or graded response. For this study, we used flow cytometry and immunofluorescence to generate single-cell measurements of MAPK signaling in Swiss 3T3 fibroblasts. In contrast to the case in Xenopus oocytes, we found that ERK activation in individual mammalian cells is not ultrasensitive and shows a graded response to changes in agonist concentration. Thus, the conserved MAPK signaling module exhibits different systems-level properties in different cellular contexts. Furthermore, the graded ERK response was converted into a more switch-like behavior at the level of immediate-early gene induction and cell cycle progression. Thus, while MAPK signaling is involved in all-or-nothing cell fate decisions for both Xenopus oocyte maturation and mammalian fibroblast proliferation, the underlying mechanisms responsible for the switch-like nature of the cellular responses are different in these two systems, with the mechanism appearing to lie downstream of the kinase cascade in mammalian fibroblasts.

Role of nuclear factor κB and mitogen-activated protein kinase signaling in exercise-induced antioxidant enzyme adaptation

2007 ◽  
Vol 32 (5) ◽  
pp. 930-935 ◽  
Author(s):  
Li Li Ji ◽  
Maria-Carmen Gomez-Cabrera ◽  
Jose Vina
Keyword(s):  
Protein Kinase ◽  
Nuclear Factor Κb ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Ros Generation ◽  
Nuclear Factor ◽  
Adaptive Responses ◽  
Wide Range ◽  
Mitogen Activated Protein ◽  
Exercise Induced

Activation of nuclear factor (NF) κB and mitogen-activated protein kinase (MAPK) pathways in skeletal muscle has been shown to enhance the gene expression of several enzymes that play an important role in maintaining oxidant–antioxidant homeostasis, such as mitochondrial superoxide dismutase (MnSOD) and inducible nitric oxide synthase (iNOS). While an acute bout of exercise activates NFκB and MAPK signaling and upregulates MnSOD and iNOS, administration of chemical agents that suppress reactive oxygen species (ROS) production can cause attenuation of exercise-induced MnSOD and iNOS expression. Thus, ROS generation during exercise may have duel effects: the infliction of oxidative stress and damage, and the stimulation of adaptive responses favoring long-term protection. This scenario explains why animals and humans involved in exercise training have demonstrated increased resistance to oxidative damage under a wide range of physiological and pathological stresses.

scholarly journals MKP-3 Has Essential Roles as a Negative Regulator of the Ras/Mitogen-Activated Protein Kinase Pathway during Drosophila Development

2004 ◽  
Vol 24 (2) ◽  
pp. 573-583 ◽  
Author(s):  
Myungjin Kim ◽  
Guang-Ho Cha ◽  
Sunhong Kim ◽  
Jun Hee Lee ◽  
Jeehye Park ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Cell Fate ◽  
Photoreceptor Cells ◽  
Mapk Signaling ◽  
Negative Regulator ◽  
Mitogen Activated Protein Kinase ◽  
Loss Of Function ◽  
Wing Vein ◽  
Mitogen Activated Protein

ABSTRACT Mitogen-activated protein kinase (MAPK) phosphatase 3 (MKP-3) is a well-known negative regulator in the Ras/extracellular signal-regulated kinase (ERK)-MAPK signaling pathway responsible for cell fate determination and proliferation during development. However, the physiological roles of MKP-3 and the mechanism by which MKP-3 regulates Ras/Drosophila ERK (DERK) signaling in vivo have not been determined. Here, we demonstrated that Drosophila MKP-3 (DMKP-3) is critically involved in cell differentiation, proliferation, and gene expression by suppressing the Ras/DERK pathway, specifically binding to DERK via the N-terminal ERK-binding domain of DMKP-3. Overexpression of DMKP-3 reduced the number of photoreceptor cells and inhibited wing vein differentiation. Conversely, DMKP-3 hypomorphic mutants exhibited extra photoreceptor cells and wing veins, and its null mutants showed striking phenotypes, such as embryonic lethality and severe defects in oogenesis. All of these phenotypes were highly similar to those of the gain-of-function mutants of DERK/rl. The functional interaction between DMKP-3 and the Ras/DERK pathway was further confirmed by genetic interactions between DMKP-3 loss-of-function mutants or overexpressing transgenic flies and various mutants of the Ras/DERK pathway. Collectively, these data provide the direct evidences that DMKP-3 is indispensable to the regulation of DERK signaling activity during Drosophila development.

scholarly journals The Repertoire of Fos and Jun Proteins Expressed during the G1 Phase of the Cell Cycle Is Determined by the Duration of Mitogen-Activated Protein Kinase Activation

1999 ◽  
Vol 19 (1) ◽  
pp. 330-341 ◽  
Author(s):  
Simon J. Cook ◽  
Natasha Aziz ◽  
Martin McMahon
Keyword(s):  
Protein Kinase ◽  
Cell Fate ◽  
Active Form ◽  
Mapk Cascade ◽  
Mitogen Activated Protein Kinase ◽  
Mapk Activation ◽  
Cell Fate Decisions ◽  
Mitogen Activated Protein ◽  
Early Expression ◽  
Fos Expression

ABSTRACT In Rat-1 fibroblasts nonmitogenic doses of lysophosphatidic acid (LPA) stimulate a transient activation of mitogen-activated protein kinase (MAPK), whereas mitogenic doses elicit a sustained response. This sustained phase of MAPK activation regulates cell fate decisions such as proliferation or differentiation, presumably by inducing a program of gene expression which is not observed in response to transient MAPK activation. We have examined the expression of members of the AP-1 transcription factor complex in response to stimulation with different doses of LPA. c-Fos, c-Jun, and JunB are induced rapidly in response to LPA stimulation, whereas Fra-1 and Fra-2 are induced after a significant lag. The expression of c-Fos is transient, whereas the expression of c-Jun, JunB, Fra-1, and Fra-2 is sustained. The early expression of c-Fos can be reconstituted with nonmitogenic doses of LPA, but the response is transient compared to that observed with mitogenic doses. In contrast, expression of Fra-1, Fra-2, and JunB and optimal expression of c-Jun are observed only with doses of LPA which induce sustained MAPK activation and DNA synthesis. LPA-stimulated expression of c-Fos, Fra-1, Fra-2, c-Jun, and JunB is inhibited by the MEK1 inhibitor PD098059, indicating that the Raf-MEK-MAPK cascade is required for their expression. In cells expressing a conditionally active form of Raf-1 (ΔRaf-1:ER), we observed that selective, sustained activation of Raf-MEK-MAPK was sufficient to induce expression of Fra-1, Fra-2, and JunB but, interestingly, induced little or no c-Fos or c-Jun. The induction of c-Fos observed in response to LPA was strongly inhibited by buffering the intracellular [Ca2+]. Moreover, although Raf activation or calcium ionophores induced little c-Fos expression, we observed a synergistic induction in response to the combination of ΔRaf-1:ER and ionomycin. These results suggest that kinetically distinct phases of MAPK activation serve to regulate the expression of distinct AP-1 components such that sustained MAPK activation is required for the induced expression of Fra-1, Fra-2, c-Jun, and JunB. However, in contrast to the case for Fra-1, Fra-2, and JunB, activation of the MAPK cascade alone is not sufficient to induce c-Fos expression, which rather requires cooperation with other signals such as Ca2+mobilization. Finally, the identification of the Fra-1, Fra-2, c-Jun, and JunB genes as genes which are selectively regulated by sustained MAPK activation or in response to activated Raf suggests that they are candidates to mediate certain of the effects of Ras proteins in oncogenic transformation.

Systems analysis of MAPK signal transduction

2008 ◽  
Vol 45 ◽  
pp. 95-108 ◽  
Author(s):  
Nils Blüthgen ◽  
Stefan Legewie
Keyword(s):  
Gene Expression ◽  
Cell Fate ◽  
Mapk Pathway ◽  
Experimental Studies ◽  
Mitogen Activated Protein Kinase ◽  
Cell Fate Decisions ◽  
Biological Responses ◽  
Mitogen Activated Protein ◽  
Kinase Cascade ◽  
Extracellular Stimuli

For more than a decade, the MAPK (mitogen-activated protein kinase) cascade has been studied using mathematical modelling and quantitative experimentation [1]. The MAPK cascade relays the presence of extracellular stimuli such as growth hormones to the nucleus and controls the expression of hundreds of genes. MAPKs control major cell fate decisions such as proliferation, differentiation and apoptosis, mainly by inducing alterations in gene expression. In this chapter, we discuss how systems biology analysis provides insights into the functioning of this cascade. We show how this pathway assists the cell in responding properly to extracellular cues by filtering out sub-threshold stimuli, while efficiently transmitting physiologically relevant inputs. Several different receptors signal through the MAPK pathway even though they elicit opposite biological responses, thus raising the question of how specificity is achieved in MAPK signalling. Experimental studies revealed that specific biological responses are encoded by quantitative aspects of the MAPK signal such as amplitude or duration. We discuss mechanisms that enable the pathway to generate quantitatively different signals, and also explain how different signals are interpreted by the downstream gene expression machinery.

scholarly journals KSR1 Modulates the Sensitivity of Mitogen-Activated Protein Kinase Pathway Activation in T Cells without Altering Fundamental System Outputs

2009 ◽  
Vol 29 (8) ◽  
pp. 2082-2091 ◽  
Author(s):  
Joseph Lin ◽  
Angus Harding ◽  
Emanuele Giurisato ◽  
Andrey S. Shaw
Keyword(s):  
T Cells ◽  
T Cell ◽  
Protein Kinase ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Mapk Activation ◽  
Cell Fate Decisions ◽  
Mapk Cascades ◽  
Wide Range ◽  
Mitogen Activated Protein

ABSTRACT Mitogen-activated protein kinase (MAPK) cascades are evolutionarily conserved signaling pathways that regulate cell fate decisions. They generate a wide range of signal outputs, including graded and digital responses. In T cells, MAPK activation is digital in response to T-cell-receptor stimulation; however, whether other receptors on T cells that lead to MAPK activation are graded or digital is unknown. Here we evaluate MAPK activation in T cells at the single-cell level. We show that T cells responded digitally to stimulation with superantigen-loaded antigen-presenting cells, whereas they responded in a graded manner to the chemokine SDF-1, demonstrating that the system output of the MAPK module is highly plastic and determined by components upstream of the MAPK module. These findings also confirm that different MAPK system outputs are used by T cells to control discrete biological functions. Scaffold proteins are essential for proper MAPK signaling and function as they physically assemble multiple components and regulators of MAPK cascades. We found that the scaffold protein KSR1 regulated the threshold required for MAPK activation in T cells without affecting the nature of the response. We conclude that KSR1 plays a central role in determining the sensitivity of T-cell responses and is thus well positioned as a key control point.

scholarly journals An unexpected bifurcation in the Pointed transcriptional effector network contributes specificity and robustness to retinal cell fate acquisition

2020 ◽  
Author(s):  
Chudong Wu ◽  
Jean-François Boisclair Lachance ◽  
Michael Z Ludwig ◽  
Ilaria Rebay
Keyword(s):  
Cell Fate ◽  
Expression Patterns ◽  
Active Form ◽  
Transcriptional Response ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Retinal Cell ◽  
Intrinsic Activity ◽  
Regulatory Interactions ◽  
Mitogen Activated Protein

AbstractSpatiotemporally specific and robust cell fate transitions are fundamental to the development of appropriately patterned tissues. In the Drosophila retina, receptor tyrosine kinase / mitogen activated protein kinase (MAPK) signaling acts through the transcriptional effector Pointed (Pnt) to direct two distinct rounds of photoreceptor specification. A relay mechanism between two Pnt isoforms, a MAPK responsive form PntP2 and a constitutively active form PntP1, initiates and sustains the transcriptional response. Here, we report an unexpected bifurcation in the Pnt effector network. We show that PntP2 works redundantly with a closely related but previously uncharacterized isoform, PntP3, to activate pntP1 during specification of first round photoreceptors. Intrinsic activity differences between PntP2 and PntP3, combined with positive and negative transcriptional auto- and cross-regulation, buffer first-round fates against conditions of low signaling. In contrast, in a mechanism that may be adaptive to the stronger signaling environment used to specify second round fates, PntP2 uniquely activates pntP1. We propose that differences in expression patterns, transcriptional activities and regulatory interactions between Pnt isoforms together facilitate context-appropriate cell fate specification in different signaling environments.

scholarly journals Selective Regulation of c-jun Gene Expression by Mitogen-Activated Protein Kinases via the 12-O-Tetradecanoylphorbol-13-Acetate- Responsive Element and Myocyte Enhancer Factor 2 Binding Sites

2005 ◽  
Vol 25 (9) ◽  
pp. 3784-3792 ◽  
Author(s):  
Midori Kayahara ◽  
Xin Wang ◽  
Cathy Tournier
Keyword(s):  
Gene Expression ◽  
Protein Kinase ◽  
Cell Fate ◽  
P38 Mapk ◽  
Physiological Role ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Mapk Cascades ◽  
Mitogen Activated Protein

ABSTRACT To further understand how the mitogen-activated protein kinase (MAPK) signaling pathways regulate AP-1 activity, we have elucidated the physiological role of these cascades in the regulation of c-jun gene expression. c-Jun is a crucial component of AP-1 complexes and has been shown in vitro to be a point of integration of numerous signals that can differentially affect its expression as well as its transcriptional activity. Our strategy was based on the use of (i) genetically modified fibroblasts deficient in components of the MAPK cascades and (ii) pharmacological reagents. The results demonstrate that c-Jun NH2-terminal protein kinase (JNK) is essential for a basal level of c-Jun expression and for c-Jun phosphorylation in response to stress. In addition to JNK, p38 MAPK or ERK1/2 and ERK5 are required for mediating UV radiation- or epidermal growth factor (EGF)-induced c-Jun expression, respectively. Further studies indicate that p38 MAPK inhibits the activation of JNK in response to EGF, causing a down-regulation of c-Jun. Overall, these data provide important insights into the mechanisms that ultimately determine the function of c-Jun as a regulator of cell fate.

scholarly journals A Network of Immediate Early Gene Products Propagates Subtle Differences in Mitogen-Activated Protein Kinase Signal Amplitude and Duration

2004 ◽  
Vol 24 (1) ◽  
pp. 144-153 ◽  
Author(s):  
Leon O. Murphy ◽  
Jeffrey P. MacKeigan ◽  
John Blenis
Keyword(s):  
Protein Kinase ◽  
Cell Fate ◽  
Signal Amplitude ◽  
Immediate Early Gene ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Early Gene ◽  
Immediate Early ◽  
General Mechanism ◽  
Mitogen Activated Protein

ABSTRACT The strength and duration of mitogen-activated protein kinase (MAPK) signaling have been shown to regulate cell fate in different cell types. In this study, a general mechanism is described that explains how subtle differences in signaling kinetics are translated into a specific biological outcome. In fibroblasts, the expression of immediate early gene (IEG)-encoded Fos, Jun, Myc, and early growth response gene 1 (Egr-1) transcription factors is significantly extended by sustained extracellular signal-regulated kinase 1 and 2 (ERK1 and -2) signaling. Several of these proteins contain functional docking site for ERK, FXFP (DEF) domains that serve to locally concentrate the active kinase, thus showing that they can function as ERK sensors. Sustained ERK signaling regulates the posttranslational modifications of these IEG-encoded sensors, which contributes to their sustained expression during the G1-S transition. DEF domain-containing sensors can also interpret the small changes in ERK signal strength that arise from less than a threefold reduction in agonist concentration. As a result, downstream target gene expression and cell cycle progression are significantly changed.

scholarly journals Specific Functional Features of the Cell Integrity MAP Kinase Pathway in the Dimorphic Fission Yeast Schizosaccharomyces japonicus

2021 ◽  
Vol 7 (6) ◽  
pp. 482
Author(s):  
Elisa Gómez-Gil ◽  
Alejandro Franco ◽  
Beatriz Vázquez-Marín ◽  
Francisco Prieto-Ruiz ◽  
Armando Pérez-Díaz ◽  
...  
Keyword(s):  
Fission Yeast ◽  
Environmental Changes ◽  
Yeast Species ◽  
Mapk Signaling ◽  
Fine Tuning ◽  
Mitogen Activated Protein Kinase ◽  
Major Influence ◽  
Cell Integrity ◽  
Mitogen Activated Protein ◽  
Functional Features

Mitogen activated protein kinase (MAPK) signaling pathways execute essential functions in eukaryotic organisms by transducing extracellular stimuli into adaptive cellular responses. In the fission yeast model Schizosaccharomyces pombe the cell integrity pathway (CIP) and its core effector, MAPK Pmk1, play a key role during regulation of cell integrity, cytokinesis, and ionic homeostasis. Schizosaccharomyces japonicus, another fission yeast species, shows remarkable differences with respect to S. pombe, including a robust yeast to hyphae dimorphism in response to environmental changes. We show that the CIP MAPK module architecture and its upstream regulators, PKC orthologs Pck1 and Pck2, are conserved in both fission yeast species. However, some of S. pombe’s CIP-related functions, such as cytokinetic control and response to glucose availability, are regulated differently in S. japonicus. Moreover, Pck1 and Pck2 antagonistically regulate S. japonicus hyphal differentiation through fine-tuning of Pmk1 activity. Chimeric MAPK-swapping experiments revealed that S. japonicus Pmk1 is fully functional in S. pombe, whereas S. pombe Pmk1 shows a limited ability to execute CIP functions and promote S. japonicus mycelial development. Our findings also suggest that a modified N-lobe domain secondary structure within S. japonicus Pmk1 has a major influence on the CIP signaling features of this evolutionarily diverged fission yeast.

Sign in / Sign up

Export Citation Format

Share Document