Related Experiment Video
Updated: Jun 2, 2026
08:51
The Microscopy-Based Assay to Study and Analyze the Recycling Endosomes using SNARE Trafficking
Published on: February 12, 2022
Important relationships between Rab and MICAL proteins in endocytic trafficking
Juliati Rahajeng1, Sai Srinivas Panapakkam Giridharan, Bishuang Cai
1Juliati Rahajeng, Sai Srinivas Panapakkam Giridharan, Bishuang Cai, Naava Naslavsky, Steve Caplan, Department of Biochemistry and Molecular Biology, and Eppley Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198-5870, United States.
World Journal of Biological Chemistry
|May 4, 2011
Summary
This review highlights the roles of MICAL and Rab proteins in endocytic transport. Their interactions are crucial for regulating nutrient and receptor recycling in eukaryotic cells.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Endocytosis is a vital process for eukaryotic cells, involving the internalization and sorting of nutrients, lipids, and receptors.
- Rab proteins, small GTP-binding proteins, regulate intracellular trafficking pathways by cycling between GDP-bound and GTP-bound states.
- Eps15 homology (EHD) proteins are involved in endocytic regulation, with some interacting with Rab effector proteins.
Purpose of the Study:
- To summarize the functional roles of MICAL and Rab proteins in endocytic transport.
- To focus on the significance of interactions between MICAL and Rab proteins.
- To explore the implications of these interactions for endocytic pathways.
Main Methods:
- Literature review of studies on MICAL and Rab proteins.
- Analysis of protein-protein interactions between MICAL and Rab effectors.
- Examination of the roles of MICAL-L1 and MICAL-L2 in endocytic recycling and cytoskeletal regulation.
Main Results:
- MICAL-like proteins, such as MICAL-L1 and MICAL-L2, share interaction partners with Rab proteins.
- These proteins are implicated in the endocytic recycling of cell surface receptors and junctional proteins.
- MICAL proteins also play roles in cytoskeletal rearrangement and neurite outgrowth.
Conclusions:
- The interaction between MICAL and Rab proteins is significant for regulating endocytic transport.
- Understanding these interactions provides insights into the mechanisms of receptor sorting and recycling.
- MICAL and Rab proteins are key regulators of fundamental cellular processes.
Related Concept Videos
01:25Rab 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.
01:14Rab 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 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...
01:28The Early Endosome: Endocytosis of Transferrin
Essential proteins such as insulin or low-density lipoprotein (LDL) and micronutrients such as iron enter a eukaryotic cell through receptor-mediated endocytosis. Subsequently, the early endosomes fuse with the vesicles containing such receptor-ligand complexes and play a vital role in sorting the incoming ligands and receptors. While the ligands are either degraded inside the vesicle or released into the cytosol, their receptors are returned to the plasma membrane for further rounds of...
00:58Recycling Endosomes and Transcytosis
The recycling endosome, also known as the endosomal recycling compartment (ERC), is a part of the slow-recycling process of the endocytic pathway. Molecules internalized through receptor-mediated endocytosis are either degraded in the lysosomes or are recycled to the plasma membrane through the fast- or slow-recycling route.
The recycling endosome is not a single organelle but an extensively tubulated network of recycling pathways. It functions in storing molecules or transporting them across...
The recycling endosome is not a single organelle but an extensively tubulated network of recycling pathways. It functions in storing molecules or transporting them across...
01:43SNAREs and Membrane Fusion
Once a transport vesicle has recognized its target organelle, the vesicular membrane needs to fuse with the target membrane to unload the cargo. Transmembrane proteins called SNAREs present on organelle membranes and their vesicles, mediate vesicle fusion.
SNAREs exist in pairs that symmetrically interact and catalyze the fusion of the lipid bilayers in vesicle and target organelle. v-SNARE in the vesicle membrane are single polypeptide chains that bind to a complementary t-SNARE, composed of 2...
SNAREs exist in pairs that symmetrically interact and catalyze the fusion of the lipid bilayers in vesicle and target organelle. v-SNARE in the vesicle membrane are single polypeptide chains that bind to a complementary t-SNARE, composed of 2...
01:38Intralumenal Vesicles and Multivesicular Bodies
Intraluminal vesicles (ILVs) are small vesicles 50-80 nm in diameter formed during the maturation of early endosomes. A specialized endosome containing numerous ILVs is called a multivesicular body (MVB). ILVs contain internalized molecules such as antigens, nucleic acids, proteins, and metabolites. Some of these molecules are released from the MVBs inside exosomes and are transported to other cells. Other MVBs contain molecules that are retained in the ILVs and are later degraded within the...