Related Experiment Video

Updated: Oct 2, 2026

Assaying Protein Kinase Activity with Radiolabeled ATP
08:05

Assaying Protein Kinase Activity with Radiolabeled ATP

Published on: May 26, 2017

Protein kinase C delta (PKCdelta) is required for protein tyrosine phosphatase mu (PTPmu)-dependent neurite outgrowth

Jullia A Rosdahl1, Tracy L Mourton, Susann M Brady-Kalnay

  • 1Department of Molecular Biology and Microbiology, Case Western Reserve University, School of Medicine, Cleveland, Ohio 44106-4960, USA.

Molecular and Cellular Neurosciences
|February 28, 2002
PubMed

Insights

Protein tyrosine phosphatase mu (PTPmu) promotes nerve cell growth by interacting with RACK1 and protein kinase C delta (PKCdelta). This signaling pathway is crucial for neurite outgrowth in retinal ganglion cells.

Area of Science:

  • Neuroscience
  • Cell Biology
  • Biochemistry

Background:

  • Protein tyrosine phosphatase mu (PTPmu) is an immunoglobulin superfamily adhesion molecule found in the developing nervous system.
  • PTPmu promotes neurite outgrowth in retinal ganglion cells and regulates N-cadherin-mediated outgrowth.
  • PTPmu interacts with the scaffolding protein RACK1, a receptor for activated protein kinase C (PKC).

Purpose of the Study:

  • To investigate the role of PKC in PTPmu-dependent signaling.
  • To determine if PKC is involved in PTPmu-mediated neurite outgrowth.

Main Methods:

  • Co-immunoprecipitation to identify protein complexes.
  • Pharmacological inhibition of PKC to assess its role in neurite outgrowth.
  • Cultured retinal cells and retinal tissue were used.

Main Results:

  • PTPmu, RACK1, and PKCdelta form a complex in retinal cells and tissue.
  • PKCdelta activity is necessary for PTPmu-dependent neurite outgrowth of retinal ganglion cells.
  • Pharmacological inhibition of PKC blocked PTPmu-mediated neurite outgrowth.

Conclusions:

  • PKC signaling, specifically involving PKCdelta, is essential for PTPmu-mediated neurite outgrowth.
  • The PTPmu-RACK1 complex likely recruits and activates PKCdelta to promote neurite extension.
  • These findings elucidate a novel signaling mechanism regulating neuronal development.

More Related Videos

Understanding the Development of Compensatory Pathways in a Mutant Malaria Parasite Harbouring Hypomorphic Allele of Plant-Like Kinases09:13

Understanding the Development of Compensatory Pathways in a Mutant Malaria Parasite Harbouring Hypomorphic Allele of Plant-Like Kinases

Published on: November 22, 2024

Related Concept Videos

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...
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...
Receptor Tyrosine Kinases01:26

Receptor Tyrosine Kinases

Receptor tyrosine kinases or RTKs are membrane-bound receptors that phosphorylate specific tyrosine on protein substrates. RTKs regulate cellular growth, differentiation, survival, and migration. They contain an extracellular ligand binding domain, a transmembrane domain, and a cytosolic tail with intrinsic kinase activity. Several extracellular signaling molecules activate RTKs in one or more ways and relay the signal downstream. Ligands such as platelet-derived growth factor (PDGF) or...
Protein Kinases and Phosphatases02:54

Protein Kinases and Phosphatases

Proteins undergo chemical modifications that trigger changes in the charge, structure, and conformation of the proteins. Phosphorylation, acetylation, glycosylation, nitrosylation, ubiquitination, lipidation, methylation, and proteolysis are various protein modifications that regulate protein activity. Such modifications are usually enzyme-driven.
Protein kinases
Many proteins in the cell are regulated by phosphorylation, the addition of a phosphate group. A family of enzymes called kinases...
Calmodulin-dependent Signaling01:16

Calmodulin-dependent Signaling

Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
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...