Related Experiment Video
Updated: Jul 6, 2025
16:33
Detection of Protein Palmitoylation in Cultured Hippocampal Neurons by Immunoprecipitation and Acyl-Biotin Exchange ABE
Published on: February 18, 2013
36.0K
Regulation of RAS palmitoyltransferases by accessory proteins and palmitoylation
Anlan Yang1,2, Shengjie Liu2,3, Yuqi Zhang2
1College of Life Sciences, Zhejiang University, Hangzhou, China.
Nature Structural & Molecular Biology
|January 5, 2024
Summary
Researchers uncovered how DHHC9-GCP16 complex catalyzes RAS palmitoylation. GCP16 stabilizes DHHC9, while phospholipid binding and specific cysteine palmitoylation are crucial for enzyme activity, revealing key regulatory insights.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Signaling
Background:
- Palmitoylation of HRAS and NRAS is essential for RAS signaling.
- DHHC9 acyltransferase, complexed with GCP16, catalyzes this critical modification.
- The precise mechanism of DHHC9 activity and GCP16 regulation remained unclear.
Purpose of the Study:
- To elucidate the structural basis of DHHC9-GCP16 complex function.
- To understand the role of GCP16 in DHHC9-mediated palmitoylation.
- To identify key factors regulating DHHC9 catalytic activity.
Main Methods:
- Cryo-electron microscopy (cryo-EM) of human DHHC9-GCP16 and yeast Erf2-Erf4 complexes.
- Biochemical assays to assess catalytic activity.
- Site-directed mutagenesis to investigate essential residues and regions.
Main Results:
- Cryo-EM structures revealed GCP16 stabilizes DHHC9 architecture, not directly participating in catalysis.
- Phospholipid binding to an arginine-rich region of DHHC9 is essential for activity.
- Palmitoylation of specific cysteine residues (C24, C25, C288) on DHHC9 is critical for catalysis.
- GCP16 also complexes with DHHC14 and DHHC18, suggesting broader roles in RAS palmitoylation.
Conclusions:
- GCP16 acts as a structural stabilizer for DHHC9, facilitating RAS palmitoylation.
- Specific structural features and post-translational modifications of DHHC9 are key determinants of its catalytic function.
- The findings provide a mechanistic understanding of RAS palmitoyltransferases regulation.
Related Concept Videos
02:38The Ras Gene
6.2K
The Ras-gene-encoded proteins are regulators of signaling pathways controlling cell proliferation, differentiation, or cell survival. The Ras-gene family in humans constitutes three primary members—the HRas, NRas, and KRas. These genes code for four functionally distinct yet closely related proteins—the HRas, NRas, KRas4A, and KRas4B. The involvement of mutant Ras genes in human cancer was first discovered in 1982 and is among the most common causes of human tumorigenesis.
Ras is a...
Ras is a...
6.2K
01:24Small GTPases - Ras and Rho
4.0K
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:
Three regulatory proteins control their activity:
4.0K
01:07MAPK Signaling Cascades
5.5K
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...
5.5K
01:22PI3K/mTOR/AKT Signaling Pathway
3.6K
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...
3.6K
01:32Lipids as Anchors
5.6K
In the plasma membrane, the lipids forming the bilayer can also act as an anchor to tether proteins to the membrane. The three main types of lipid anchors found in eukaryotes are – prenyl groups, fatty acyl groups, and glycosylphosphatidylinositol or GPI groups. Prenyl and fatty acyl groups act as anchors on the cytosolic surface of the membrane, whereas GPI anchors proteins on the extracellular side.
The carboxy-terminal of most of the prenylated proteins, such as Ras proteins, contains...
The carboxy-terminal of most of the prenylated proteins, such as Ras proteins, contains...
5.6K
01:14Rab Proteins
3.9K
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...
3.9K