Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Small GTPases - Ras and Rho

Small GTPases - Ras and Rho

Ras and Rho are small monomeric GTPases that act downstream of receptor tyrosine kinase (RTK) and regulate various cellular processes. These GTPases switch between active and inactive states by binding to guanine nucleotides.
Three regulatory proteins control their activity:

In-vitro Mutagenesis

In-vitro Mutagenesis

To learn more about the function of a gene, researchers can observe what happens when the gene is inactivated or “knocked out,” by creating genetically engineered knockout animals. Knockout mice have been particularly useful as models for human diseases such as cancer, Parkinson’s disease, and diabetes.

Activation and Inactivation of G Proteins

Activation and Inactivation of G Proteins

Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high...

Rab Cascades

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.

Rab Proteins

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...

Mouse Models of Cancer Study

Mouse Models of Cancer Study

Mice have long served as models for studying human biology and pathology because of their phylogenetic and physiological similarity with humans. They are also easy to maintain and breed in the laboratory, and hence, many inbred strains are now available for research. Studies on mice have contributed immeasurably to our understanding of cancer biology.
The development of transgenic, knockout, and knock-in mice has led to an exponential increase in their use as model organisms in research,...

You might also read

Related Articles

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

Sort by

Same author

OMA1 protects from liver injury and tumorigenesis during aging by controlling hepatic immunogenicity.

The EMBO journal·2026

Same author

SUCNR1 coordinates metabolic flux, mitochondrial function, and nutrient-dependent adaptation in hepatocytes.

Science advances·2026

Same author

Publisher Correction: Polyamine-dependent metabolic shielding regulates alternative splicing.

Nature·2026

Same author

Polyamine-dependent metabolic shielding regulates alternative splicing.

Nature·2026

Same author

Macrophages recycle phagocytosed bacteria to fuel immunometabolic responses.

Nature·2025

Same author

A mild increase in nutrient signaling to mTORC1 in mice leads to parenchymal damage, myeloid inflammation and shortened lifespan.

Nature aging·2024

Search research articles

Related Experiment Video

Updated: Oct 11, 2025

Author Spotlight: Optogenetic Inhibition of Rho1-Mediated Actomyosin Contractility Coupled with Measurement of Epithelial Tension in Drosophila Embryos

Author Spotlight: Optogenetic Inhibition of Rho1-Mediated Actomyosin Contractility Coupled with Measurement of Epithelial Tension in Drosophila Embryos

Published on: April 14, 2023

From mouse genetics to targeting the Rag GTPase pathway.

Ana Ortega-Molina¹, Alejo Efeyan¹

¹Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Centre (CNIO), Madrid, Spain.

Molecular & Cellular Oncology

|December 3, 2021

Summary

The Rag GTPases are key to nutrient signaling for the mechanistic target of rapamycin (mTOR) pathway. Mouse studies reveal insights into targeting this pathway for human disease treatment.

Keywords:

B cells Mtor Rag GTPases; nutrients lymphoma mice small molecules

More Related Videos

RiboTag Immunoprecipitation in the Germ Cells of the Male Mouse

RiboTag Immunoprecipitation in the Germ Cells of the Male Mouse

Published on: March 4, 2020

Mouse Genome Engineering Using Designer Nucleases

Mouse Genome Engineering Using Designer Nucleases

Published on: April 2, 2014

Related Experiment Videos

Last Updated: Oct 11, 2025

Author Spotlight: Optogenetic Inhibition of Rho1-Mediated Actomyosin Contractility Coupled with Measurement of Epithelial Tension in Drosophila Embryos

Author Spotlight: Optogenetic Inhibition of Rho1-Mediated Actomyosin Contractility Coupled with Measurement of Epithelial Tension in Drosophila Embryos

Published on: April 14, 2023

RiboTag Immunoprecipitation in the Germ Cells of the Male Mouse

RiboTag Immunoprecipitation in the Germ Cells of the Male Mouse

Published on: March 4, 2020

Mouse Genome Engineering Using Designer Nucleases

Mouse Genome Engineering Using Designer Nucleases

Published on: April 2, 2014

Area of Science:

Biochemistry
Molecular Biology
Genetics

Background:

The mechanistic target of rapamycin (mTOR) pathway is crucial for cellular processes.
Nutrient sensing mechanisms regulate mTOR activity.
Rag GTPases are central regulators of nutrient signaling to mTOR.

Purpose of the Study:

To elucidate the role of Rag GTPases in nutrient-mediated mTOR signaling.
To explore the potential of targeting the Rag GTPase pathway for therapeutic interventions.

Main Methods:

Utilized mouse genetic models.
Investigated pathophysiological mechanisms related to nutrient signaling.

Main Results:

Rag GTPases were identified as critical components in the nutrient-signaling cascade to mTOR.
Mouse genetic studies provided insights into the pathway's role in disease.

Conclusions:

The Rag GTPase pathway is a significant target for modulating mTOR activity.
Inhibitors of the Rag GTPase pathway show potential for treating human diseases.