Related Experiment Video

Updated: Jul 23, 2026

A High Resolution Method to Monitor Phosphorylation-dependent Activation of IRF3
11:44

A High Resolution Method to Monitor Phosphorylation-dependent Activation of IRF3

Published on: January 24, 2016

JAK3 associates with the human interleukin 4 receptor and is tyrosine phosphorylated following receptor triggering

C Rolling1, D Treton, P Beckmann

  • 1INSERM U131, Institut Paris-Sud sur les Cytokines, Clamart, France.

Oncogene
|May 4, 1995
PubMed

In human B cells, interleukin 4 (IL4) acts in regulating proliferation, antigen expression, isotype switching and differentiation. These different effects are mediated through the IL4R complex including the IL2R gamma chain (gamma c) and a specific p130/140 binding unit referred below as human Interleukin 4 Receptor (IL4-R). Here, we studied the signal transduction events following IL4R activation and leading to CD23 expression on resting B cells. We demonstrate that IL4R triggering induced the tyrosine phosphorylation of JAK3 and of a p170 protein. Coimmunoprecipitation of JAK3 with the IL4R suggests a physical association which exists prior to IL4R complex stimulation. Orthovanadate treatment, while having no effect on IL4-induced p130 phosphorylation, leads to the hyperphosphorylation of the p170 and inhibits IL4-induced CD23 expression. These suggest that two mandatory steps exist in early IL4 signaling: one controlled by JAK3 activation and the other by the p170 phosphoprotein.

More Related Videos

Phospho Flow Cytometry with Fluorescent Cell Barcoding for Single Cell Signaling Analysis and Biomarker Discovery08:38

Phospho Flow Cytometry with Fluorescent Cell Barcoding for Single Cell Signaling Analysis and Biomarker Discovery

Published on: October 4, 2018

Assessment of Human Natural Killer Cell Events Driven by FcγRIIIa Engagement in the Presence of Therapeutic Antibodies09:54

Assessment of Human Natural Killer Cell Events Driven by FcγRIIIa Engagement in the Presence of Therapeutic Antibodies

Published on: May 22, 2020

Related Concept Videos

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...
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...
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...
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...
TGF - β Signaling Pathway01:16

TGF - β Signaling Pathway

The TGF-β signaling pathway regulates cell growth, differentiation, adhesion, motility, and development. TGF-β ligands that induce TGF-β signaling are synthesized in their latent form. Several proteases or cell surface receptors such as integrins act upon the latent form, releasing the active ligand. There are three types of mammalian TGF-βs: (TGF-β1, TGF-β2, and TGF-β3) that bind as homodimers or heterodimers to TGF-β receptors. The TGF-β receptors are of three kinds RI, RII, and RIII. The RI...
Intracellular Signaling Affects Focal Adhesions01:17

Intracellular Signaling Affects Focal Adhesions

Integrins act both as extracellular input receivers and as intracellular processing activators. As their name suggests, integrins are entirely integrated into the membrane structure. Their hydrophobic membrane-spanning regions interact with the phospholipid bilayer's hydrophobic region. These membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors. They activate intracellular response cascades when their effectors are bound and active.
Some...