Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Rab Proteins01:14

Rab Proteins

Rab proteins constitute the largest family of monomeric GTPases, of which 70 members are present in humans. Rab proteins and their effectors regulate consecutive stages of vesicle transport such as vesicle transport, docking, and fusion to the correct recipient membrane.
Rab proteins switch between a cytosolic, GDP-bound inactive state and a membrane-anchored, GTP-bound active state. By themselves, Rabs show slow rates of GDP/GTP exchange and GTP hydrolysis. Thus, Rab proteins are considered...
Rab Cascades01:25

Rab Cascades

Rab GTPases act in a regulated cascade during membrane fusion, helping the lipid bilayers mix. The Rab family of proteins are active when bound to GTP, and inactive when bound to GDP. Hence, they act as guanine nucleotide-dependent molecular switches. Rab-GTP recognizes and binds to long or short-range tethering proteins to capture the target vesicle. These tethers coordinate with SNAREs on the vesicle and the target membrane to assemble the trans SNARE complex that locks the mixing bilayers.

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Role of Macrophage Dopamine Receptors in Mediating Cytokine Production: Implications for Neuroinflammation in the Context of HIV-Associated Neurocognitive Disorders.

Journal of neuroimmune pharmacology : the official journal of the Society on NeuroImmune Pharmacology·2018
Same author

TGF-β1 alters esophageal epithelial barrier function by attenuation of claudin-7 in eosinophilic esophagitis.

Mucosal immunology·2017
Same author

Optimization of cerebellar purkinje neuron cultures and development of a plasmid-based method for purkinje neuron-specific, miRNA-mediated protein knockdown.

Methods in cell biology·2016
Same author

Loss of mucosal CD103+ DCs and IL-17+ and IL-22+ lymphocytes is associated with mucosal damage in SIV infection.

Mucosal immunology·2012
Same author

Microscale Adaptive Optics: Wave-Front Control with a mu-Mirror Array and a VLSI Stochastic Gradient Descent Controller.

Applied optics·2008
Same author

Apoptotic cell death and cytokine dysregulation in human immunodeficiency virus infection: pivotal factors in disease progression.

Cell death and differentiation·2006

Related Experiment Video

Updated: Jul 24, 2026

Investigating Mast Cell Secretory Granules; from Biosynthesis to Exocytosis
16:01

Investigating Mast Cell Secretory Granules; from Biosynthesis to Exocytosis

Published on: January 26, 2015

Defective granule exocytosis in Rab27a-deficient lymphocytes from Ashen mice.

E K Haddad1, X Wu, J A Hammer

  • 1Experimental Immunology Branch, National Cancer Institute;, and.

The Journal of Cell Biology
|March 27, 2001
PubMed
Summary

Mutations in Rab27a cause immune defects by impairing cytotoxic lymphocyte function. Ashen mice, lacking Rab27a, show defective granule secretion, crucial for cell-mediated cytotoxicity.

More Related Videos

Validation of a Mouse Model to Disrupt LINC Complexes in a Cell-specific Manner
09:02

Validation of a Mouse Model to Disrupt LINC Complexes in a Cell-specific Manner

Published on: December 10, 2015

Rab10 Phosphorylation Detection by LRRK2 Activity Using SDS-PAGE with a Phosphate-binding Tag
08:55

Rab10 Phosphorylation Detection by LRRK2 Activity Using SDS-PAGE with a Phosphate-binding Tag

Published on: December 14, 2017

Related Experiment Videos

Last Updated: Jul 24, 2026

Investigating Mast Cell Secretory Granules; from Biosynthesis to Exocytosis
16:01

Investigating Mast Cell Secretory Granules; from Biosynthesis to Exocytosis

Published on: January 26, 2015

Validation of a Mouse Model to Disrupt LINC Complexes in a Cell-specific Manner
09:02

Validation of a Mouse Model to Disrupt LINC Complexes in a Cell-specific Manner

Published on: December 10, 2015

Rab10 Phosphorylation Detection by LRRK2 Activity Using SDS-PAGE with a Phosphate-binding Tag
08:55

Rab10 Phosphorylation Detection by LRRK2 Activity Using SDS-PAGE with a Phosphate-binding Tag

Published on: December 14, 2017

Area of Science:

  • Immunology
  • Cell Biology
  • Molecular Biology

Background:

  • Rab27a mutations are linked to human immune disorders.
  • Cytotoxic lymphocytes (CTLs) and natural killer (NK) cells are critical for immune defense.
  • Granule-mediated cytotoxicity is a key function of these immune cells.

Purpose of the Study:

  • To investigate the role of Rab27a in cytotoxic lymphocyte function.
  • To analyze the impact of a Rab27a splicing mutation in ashen mice on immune cell activity.
  • To elucidate the specific mechanism by which Rab27a influences cytotoxic T lymphocyte (CTL) and NK cell function.

Main Methods:

  • Comparative analysis of cytotoxic activity in ashen mice and control C3H mice.
  • Assessment of FasL-Fas mediated cytotoxicity pathway.
  • Evaluation of T cell phenotype, proliferation, and cytokine secretion (interferon-gamma).
  • Analysis of perforin and granzyme levels and granule morphology.
  • Investigation of granule exocytosis and secretion defects upon T cell receptor stimulation.

Main Results:

  • Ashen CTLs exhibited a >90% reduction in lytic activity against Fas-negative target cells.
  • Ashen NK cell activity was also significantly diminished.
  • The granule-mediated cytotoxicity pathway was profoundly defective in ashen CTLs.
  • However, the FasL-Fas cytotoxicity pathway remained normal in ashen CTLs.
  • Granule secretion upon anti-CD3 stimulation was drastically impaired in both CD8(+) and CD4(+) T cells from ashen mice.
  • Perforin and granzymes A/B levels and granule polarization were normal, but exocytosis was defective.
  • Interferon-gamma secretion via the constitutive pathway was unaffected.

Conclusions:

  • Rab27a is essential for a late step in granule exocytosis in cytotoxic lymphocytes.
  • The protein plays a critical role in the docking and fusion of cytotoxic granules.
  • Defects in Rab27a function lead to impaired cell-mediated immunity due to defective granule release.