Related Experiment Video

Updated: Jun 9, 2026

Assaying Protein Kinase Activity with Radiolabeled ATP
08:05

Assaying Protein Kinase Activity with Radiolabeled ATP

Published on: May 26, 2017

Scaffolding proteins and non-proliferative functions of ERK1/2

Sarah Appel1, Kathleen G Morgan

  • 1Department of Health Sciences; Boston University; Boston, MA USA.

Communicative & Integrative Biology
|August 28, 2010
PubMed

Insights

Calponin acts as a novel scaffold protein, regulating extracellular signal-regulated kinases 1 and 2 (ERK1/2) in the cytosol. This localization influences cellular contraction and migration, offering new insights into signal transduction pathways.

Area of Science:

  • Cellular Biology
  • Molecular Signaling
  • Biochemistry

Background:

  • Extracellular signal-regulated kinases 1 and 2 (ERK1/2) primarily studied for nuclear functions.
  • Cytosolic roles of ERK1/2 and their regulation are less understood.
  • Scaffolding proteins are known to modulate ERK1/2 activation timing and location.

Purpose of the Study:

  • To investigate the role of scaffolding proteins in cytosolic ERK1/2 regulation.
  • To identify novel scaffolding proteins involved in ERK1/2 signaling.
  • To explore the link between cytosolic ERK1/2 and cellular contractile/migratory functions.

Main Methods:

  • Investigated the F-actin binding protein calponin as a potential ERK1/2 scaffold.
  • Utilized cell-based assays to examine ERK1/2 localization and activation.
  • Analyzed the impact of calponin on ERK1/2 substrates related to cell mechanics.

Main Results:

  • Presented evidence that calponin functions as a novel scaffold for ERK1/2.
  • Demonstrated that calponin specifically controls a subfraction of ERK1/2 in the cytosol.
  • Showed this calponin-mediated ERK1/2 activation is linked to cellular contractile and migratory processes.

Conclusions:

  • Calponin is a new type of ERK1/2 scaffold protein.
  • Calponin directs ERK1/2 activity towards cytoskeletal functions, specifically contraction and migration.
  • This discovery highlights the importance of scaffolding proteins in compartmentalizing signal transduction for specific cellular outcomes.
Keywords:
ERK1/2 signalingSmAVcalponincell migrationcytoskeleton

More Related Videos

Spatial and Temporal Analysis of Active ERK in the C. elegans Germline08:40

Spatial and Temporal Analysis of Active ERK in the C. elegans Germline

Published on: November 29, 2016

Induction and Analysis of Epithelial to Mesenchymal Transition10:37

Induction and Analysis of Epithelial to Mesenchymal Transition

Published on: August 27, 2013

Related Concept Videos

MAPK Signaling Cascades01:07

MAPK Signaling Cascades

Mitogen-activated protein kinase, or MAPK pathway, activates three sequential kinases to regulate cellular responses such as proliferation, differentiation, survival, and apoptosis. The canonical MAPK pathway starts with a mitogen or growth factor binding to an RTK. The activated RTKs stimulate Ras, which recruits Raf or MAP3 Kinase (MAPKKK), the first kinase of the MAPK signaling cascade. Raf further phosphorylates and activates MEK or MAP2 Kinases (MAPKK), which in turn phosphorylates MAP...
Assembly of Signaling Complexes01:30

Assembly of Signaling Complexes

Multiprotein signaling complexes are formed in a dynamic process involving protein-protein interactions at the cytoplasmic domain of transmembrane receptors or enzymatic and non-enzymatic proteins associated with the receptor. These complexes ensure the activation and propagation of intracellular signals that regulate cell functions.
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
Amplifying Signals via Enzymatic Cascade01:22

Amplifying Signals via Enzymatic Cascade

When a ligand binds to a cell-surface receptor, the receptor's intracellular domain changes shape, which may either activate its enzyme function or allow its binding to other molecules. The initial signal is amplified by most signal transduction pathways. This means that a single ligand molecule can activate multiple molecules of a downstream target. Proteins that relay a signal are most commonly phosphorylated at one or more sites, activating or inactivating the protein. Kinases catalyze the...
PI3K/mTOR/AKT Signaling Pathway01:22

PI3K/mTOR/AKT Signaling Pathway

The mammalian target of rapamycin  (mTOR) is a serine/threonine kinase that regulates growth, proliferation, and cell survival in response to hormones, growth factors, or nutrient availability. This kinase exists in two structurally and functionally distinct forms: mTOR complex 1  (mTORC1) and mTOR complex 2  (mTORC2). The first form (mTORC1) is composed of a rapamycin-sensitive Raptor and proline-rich Akt substrate, PRAS40. In contrast,  mTORC2 consists of a rapamycin-insensitive companion...
Interactions Between Signaling Pathways01:19

Interactions Between Signaling Pathways

Signaling cascades usually lack linearity. Multiple pathways interact and regulate one another, allowing cells to integrate and respond to diverse environmental stimuli.
Convergence and divergence, and cross-talk between signaling pathways
Two distinct signaling pathways can converge on a single functional unit, which may either be a single protein or a complex of proteins. The response is either functionally distinct or synergistic between the two pathways but different from the response...
The JAK-STAT Signaling Pathway01:20

The JAK-STAT Signaling Pathway

Several cytokine receptors have tightly bound Janus kinase or JAK proteins attached at their cytosolic tail. Small signaling molecules such as cytokines, growth hormones, or prolactins bind to the cytokine receptors and initiate their dimerization. The dimerization brings the cytosolic JAKs together that trans-phosphorylate and activates each other. The activated JAKs now phosphorylate cytosolic tails of the cytokine receptors, which serve as binding sites for adaptor proteins such as  SH2...