Related Experiment Video

Updated: May 22, 2026

A Method for Screening and Validation of Resistant Mutations Against Kinase Inhibitors
12:40

A Method for Screening and Validation of Resistant Mutations Against Kinase Inhibitors

Published on: December 7, 2014

JAK2 V617F down-modulates MPL

Angela G Fleischman1, Jeffrey W Tyner

  • 1Oregon Health & Science University.

Blood
|May 19, 2012
PubMed

Insights

The thrombopoietin receptor (MPL) is decreased in myelofibrosis. A new study shows the JAK2V617F mutation downregulates MPL expression on platelets and megakaryocytes.

Area of Science:

  • Hematology
  • Molecular Biology

Background:

  • Decreased thrombopoietin receptor (MPL) expression is a known characteristic of myelofibrosis.
  • The precise mechanism behind this downregulation has remained unclear.

Discussion:

  • This study elucidates that the JAK2V617F mutation is responsible for the reduced MPL expression.
  • Investigates the molecular mechanisms linking JAK2V617F to MPL downregulation.

Key Insights:

  • MPL expression is significantly downregulated in the presence of the JAK2V617F mutant protein.
  • Provides a mechanistic explanation for reduced MPL on platelets and megakaryocytes in myelofibrosis.

Outlook:

  • Further research into JAK2V617F-mediated MPL regulation may reveal new therapeutic targets.
  • Understanding this mechanism could lead to improved treatments for myelofibrosis.

More Related Videos

Transduction-Transplantation Mouse Model of Myeloproliferative Neoplasm08:12

Transduction-Transplantation Mouse Model of Myeloproliferative Neoplasm

Published on: December 22, 2016

Related Concept Videos

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...
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...
cAMP-dependent Protein Kinase Pathways01:25

cAMP-dependent Protein Kinase Pathways

Cyclic Adenosine Monophosphate (cAMP) is an essential second messenger that activates protein kinase A (PKA) and regulates various biological processes. A single epinephrine molecule binds to GPCR and activates several heterotrimeric G proteins, each stimulating multiple adenylyl cyclase, amplifying the signal, and synthesizing large numbers of cAMP molecules. Small changes in cAMP concentration affect PKA activity. The binding of four cAMP molecules induces a conformational change in PKA,...
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...
Receptor Downregulation in MVBs01:15

Receptor Downregulation in MVBs

Multivesicular bodies (MVBs) are mature endosomes that sort ubiquitinated proteins and then fuse with lysosomes to degrade the sorted proteins. Epidermal growth factor (EGF) and its receptor (EGFR) form a complex that can be internalized through endocytosis, sorted into an MVB, and later degraded.
The EGFR can initiate signaling pathways that  lead to cell proliferation, migration, and differentiation. Overexpression of EGFR  stimulates cells to proliferate. Excessive  EGFR activation may...
Notch Signaling Pathway03:14

Notch Signaling Pathway

The Notch signaling pathway is a major intracellular signaling pathway that is highly conserved over a broad spectrum of metazoan species. It stands unique from other intracellular signaling mechanisms in animals because notch protein itself acts as the receptor as well as the primary signaling molecule.
The Notch gene came into the limelight in 1914 after the discovery that its mutation in Drosophila melanogaster leads to a serrated (or "notched") wing margin phenotype. It was not until 1985...