GO:1905143 eukaryotic translation initiation factor 2 complex assembly: Protein Synthesis Pathway, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:1905143 describes the biological process of assembling the eukaryotic translation initiation factor 2 (eIF2) complex, a heterotrimer of eIF2α, eIF2β, and eIF2γ.
• eIF2 complex assembly is a stepwise process that can be reconstituted in vitro and is coupled to co-translational assembly of initiation factor complexes [1, 6].
• The eIF2 complex delivers the initiator methionyl-tRNA to the ribosome and is a key target of the integrated stress response (ISR) [4, 5].
• Dysregulation of eIF2 complex assembly and function is linked to cancer, neurodegeneration, and metabolic stress [2, 3, 4, 5].
• Studying GO:1905143 requires methods such as Ribo-seq, selective translation complex profiling, and proteomics.
• CRISPR-based models (knockout, point mutation, knock-in, overexpression) enable causal interrogation of eIF2 assembly genes [1, 2].
Description
Eukaryotic translation initiation factor 2 (eIF2) is a heterotrimeric GTPase that delivers the initiator methionyl-tRNA to the 40S ribosomal subunit, a critical step in cap-dependent translation initiation. The assembly of this complex, formally annotated as GO:1905143 (eukaryotic translation initiation factor 2 complex assembly), ensures that the three subunits—eIF2α, eIF2β, and eIF2γ—are correctly aggregated and bonded into a functional trimer. This process is not merely a housekeeping event; it is tightly regulated and integrated with cellular stress responses, including the integrated stress response (ISR) and mitochondrial stress signaling [4, 5]. Researchers study GO:1905143 to understand how translation is controlled under normal and pathological conditions, and to identify therapeutic targets in cancer, neurodegeneration, and metabolic disorders [2, 3, 4, 5].
eukaryotic translation initiation factor 2 complex assembly At A Glance
| GO ID | GO:1905143 |
|---|---|
| GO term | eukaryotic translation initiation factor 2 complex assembly |
| Ontology | biological_process |
| Synonym | eIF2 assembly, eIF-2 assembly, eIF2 formation, eIF-2 formation, eukaryotic translation initiation factor 2 complex formation |
| Major function | Assembly of the eIF2 heterotrimer (α, β, γ subunits) for translation initiation |
| Related process | Translation initiation, integrated stress response [4, 5] |
| Cellular context | Cytoplasm; co-translational assembly with initiation factor complexes |
| Research methods | Ribo-seq, selective translation complex profiling, proteomics |
What Is GO:1905143?
GO:1905143 is defined as the aggregation, arrangement, and bonding together of a set of components to form a eukaryotic translation initiation factor 2 complex. In simpler terms, it is the assembly of the eIF2 heterotrimer from its individual subunits, a process that can occur stepwise and is essential for translation initiation.
Why Is eukaryotic translation initiation factor 2 complex assembly Important in Cell Biology?
The assembly of the eIF2 complex is a prerequisite for translation initiation, and its dysregulation has profound consequences for cell survival and disease. The eIF2 complex is a central node in the integrated stress response, which couples mitochondrial protein translation with oxidative stress control. Moreover, ER and nutrient stress promote assembly of respiratory chain supercomplexes through the PERK-eIF2α axis, highlighting the broad impact of eIF2 assembly on cellular metabolism. Understanding GO:1905143 therefore provides insights into fundamental translation control and offers potential therapeutic avenues for cancer, neurodegeneration, and metabolic diseases [2, 3, 4, 5].
• eIF2 complex assembly is essential for delivering initiator tRNA to the ribosome, a rate-limiting step in protein synthesis.
• The process is coupled to co-translational assembly of initiation factor complexes, ensuring efficient translation.
• Dysregulation of eIF2 assembly contributes to cancer progression and tumorigenesis.
• eIF2 assembly is linked to cardiomyocyte ferroptosis in acute myocardial ischemia injury.
• The integrated stress response, which depends on eIF2, couples mitochondrial protein translation with oxidative stress control.
• ER and nutrient stress promote respiratory chain supercomplex assembly through the PERK-eIF2α axis.
• Selective translation complex profiling reveals staged initiation and co-translational assembly of initiation factor complexes.
• Mitoribosomal small subunit biogenesis and preinitiation involve eIF2-like mechanisms.
• Membrane Atg8ylation, stress granule formation, and MTOR regulation are linked to eIF2 signaling.
What Happens During eukaryotic translation initiation factor 2 complex assembly?
Stepwise assembly of the eIF2 heterotrimer
In simple terms: The three subunits of eIF2 come together in a specific order to form a working complex.
The eIF2 complex is composed of three subunits: eIF2α, eIF2β, and eIF2γ. In vitro reconstitution studies have shown that assembly proceeds stepwise, with specific subunit interactions driving the formation of the heterotrimer. This ordered assembly ensures that the complex is functional for translation initiation.
Co-translational assembly with initiation factor complexes
In simple terms: eIF2 is built while other translation factors are also being assembled, like a coordinated factory line.
Selective translation complex profiling has revealed that eIF2 assembly occurs co-translationally, coupled with the assembly of other initiation factor complexes. This staged initiation ensures that the translation machinery is assembled efficiently and correctly.
Integration with the integrated stress response (ISR)
In simple terms: When cells are stressed, eIF2 assembly and function are adjusted to help the cell cope.
The integrated stress response couples mitochondrial protein translation with oxidative stress control, and eIF2 is a key effector. Phosphorylation of eIF2α regulates this response, affecting the assembly and activity of the eIF2 complex.
Role in ER and nutrient stress
In simple terms: Stress in the ER or lack of nutrients triggers eIF2 assembly to help the cell adapt.
ER and nutrient stress promote assembly of respiratory chain supercomplexes through the PERK-eIF2α axis. This highlights how eIF2 assembly is integrated with cellular stress signaling pathways.
Mitoribosomal small subunit biogenesis and preinitiation
In simple terms: Even mitochondrial ribosomes use similar assembly principles involving eIF2-like factors.
Mechanistic studies of mitoribosomal small subunit biogenesis and preinitiation have revealed parallels with eIF2 complex assembly. These findings expand our understanding of translation initiation across cellular compartments.
Key Genes Involved in GO:1905143 eukaryotic translation initiation factor 2 complex assembly
The following genes and proteins are central to the assembly and function of the eukaryotic translation initiation factor 2 complex.
| Gene | Major Role | Research Relevance |
|---|---|---|
| EIF2S1 | Encodes eIF2α subunit; target of ISR phosphorylation | Stress response, cancer, neurodegeneration [4, 5] |
| EIF2S2 | Encodes eIF2β subunit; interacts with eIF2γ and GTP | Translation initiation, assembly studies |
| EIF2S3 | Encodes eIF2γ subunit; GTPase domain | Assembly, mitoribosome biogenesis [1, 7] |
| EIF2B1 | eIF2B subunit; guanine nucleotide exchange factor | Regulation of eIF2 activity |
| EIF2B2 | eIF2B subunit; GEF complex | ISR regulation |
| EIF2B3 | eIF2B subunit; GEF complex | Translation control |
| EIF2B4 | eIF2B subunit; GEF complex | ISR and disease |
| EIF2B5 | eIF2B subunit; GEF complex | Leukoencephalopathy |
| EIF2AK1 | HRI kinase; phosphorylates eIF2α | Stress response |
| EIF2AK2 | PKR kinase; phosphorylates eIF2α | Antiviral response |
| EIF2AK3 | PERK kinase; phosphorylates eIF2α | ER stress, supercomplex assembly |
| EIF2AK4 | GCN2 kinase; phosphorylates eIF2α | Amino acid starvation |
| METTL16 | m6A-independent function in translation | Cancer, tumorigenesis |
| ALDH2 | Interacts with eIF3E; modulates translation | Cardiomyocyte ferroptosis |
| EIF3E | eIF3 subunit; interacts with ALDH2 | Translation, ferroptosis |
| MTOR | Regulates translation and stress granule formation | Lysosomal damage response |
| ATG8 | Membrane Atg8ylation; stress granule formation | Autophagy, stress response |
How Is eukaryotic translation initiation factor 2 complex assembly Regulated?
The assembly and activity of the eIF2 complex are regulated by multiple signaling pathways. The integrated stress response (ISR) couples mitochondrial protein translation with oxidative stress control through eIF2α phosphorylation. ER and nutrient stress promote assembly of respiratory chain supercomplexes via the PERK-eIF2α axis. Additionally, mTOR signaling regulates stress granule formation and lysosomal damage responses, indirectly influencing translation initiation. These regulatory mechanisms ensure that eIF2 complex assembly is finely tuned to cellular conditions.
eukaryotic translation initiation factor 2 complex assembly and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| EIF2S1 | Cancer, neurodegeneration | Knockout, point mutation (S51A) |
| EIF2S2 | Translation initiation defects | Knockout, knock-in |
| EIF2S3 | Mitoribosome biogenesis defects | Knockout, overexpression |
| METTL16 | Cancer, tumorigenesis | Knockout, overexpression |
| ALDH2 | Cardiomyocyte ferroptosis | Knockout, point mutation |
Cancer
Dysregulation of eIF2 complex assembly and function contributes to tumorigenesis. METTL16 exerts an m6A-independent function to facilitate translation and tumorigenesis, linking eIF2-related translation to cancer. Targeting eIF2 assembly pathways may offer therapeutic opportunities in oncology.
Cardiovascular disease
ALDH2/eIF3E interaction modulates protein translation critical for cardiomyocyte ferroptosis in acute myocardial ischemia injury. This highlights the role of translation initiation factors in heart disease and ferroptosis.
Neurodegeneration
The integrated stress response, which depends on eIF2 complex assembly and phosphorylation, is implicated in neurodegenerative diseases. Dysregulation of eIF2 signaling can lead to neuronal dysfunction and death.
Metabolic and ER stress disorders
ER and nutrient stress promote assembly of respiratory chain supercomplexes through the PERK-eIF2α axis, linking eIF2 assembly to metabolic disorders. This pathway is critical for cellular adaptation to stress.
From eukaryotic translation initiation factor 2 complex assembly-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does EIF2S1 knockout affect translation initiation? | CRISPR knockout in HeLa or HEK293T cells |
| Does eIF2α S51A point mutation block ISR? | Point mutation knock-in |
| Can tagged eIF2γ be used to track assembly? | Tagged knock-in |
| Does METTL16 overexpression promote tumorigenesis? | Overexpression in cancer cell lines |
| Does ALDH2 knockout alter ferroptosis? | Knockout in cardiomyocytes |
| Does PERK-eIF2α axis regulate supercomplex assembly? | Knockout of EIF2AK3 |
How to Study the eukaryotic translation initiation factor 2 complex assembly Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Ribo-seq | Genome-wide translation efficiency | eIF2 assembly impact on translation |
| Selective translation complex profiling | Staged initiation and co-translational assembly | Initiation factor complex assembly |
| Affinity purification-MS | Protein-protein interactions | eIF2 subunit interactions |
| Western blot | Protein expression and phosphorylation | eIF2α phosphorylation status |
| Immunofluorescence | Subcellular localization | eIF2 subunit localization |
| CRISPR knockout | Gene function loss | EIF2S1, EIF2S2, EIF2S3 [1, 2] |
| CRISPR knock-in | Tagged or mutant protein expression | eIF2γ tagging |
| Overexpression | Gain-of-function | METTL16, ALDH2 [2, 3] |
Ribo-seq and translation profiling
Ribosome profiling (Ribo-seq) measures genome-wide translation efficiency and can reveal changes in eIF2 complex assembly and function. Selective translation complex profiling provides staged initiation and co-translational assembly insights.
Proteomics and interactomics
Affinity purification coupled with mass spectrometry can identify eIF2 complex components and assembly intermediates. Proteomic approaches reveal dynamic changes in eIF2 subunit interactions under stress.
Imaging and live-cell assays
Fluorescence microscopy and live-cell imaging can track the localization and assembly of eIF2 subunits in real time. Stress granule formation can be monitored as a readout of eIF2 signaling.
Genetic and biochemical reconstitution
In vitro reconstitution of eIF2 complex assembly using purified subunits allows detailed mechanistic studies. CRISPR-based genetic models enable functional validation of assembly factors [2, 3].
How CRISPR Can Be Used to Study GO:1905143 eukaryotic translation initiation factor 2 complex assembly
Knockout
CRISPR knockout of EIF2S1, EIF2S2, or EIF2S3 can abolish eIF2 complex assembly, leading to severe translation defects. Such models are useful for studying the essentiality of each subunit.
Point Mutation
Point mutations such as eIF2α S51A prevent phosphorylation and block the integrated stress response, allowing dissection of specific signaling events.
Knock-in
Knock-in of tagged eIF2 subunits (e.g., GFP or FLAG) enables live-cell imaging and affinity purification of assembly intermediates.
Overexpression
Overexpression of eIF2 subunits or regulators like METTL16 can drive tumorigenesis and reveal gain-of-function phenotypes.
How EDITGENE Supports eukaryotic translation initiation factor 2 complex assembly Research
Researchers studying eukaryotic translation initiation factor 2 complex assembly-related genes often need to determine whether a candidate gene is causally involved in the assembly process or its downstream effects. EDITGENE provides comprehensive CRISPR-based services to accelerate this research.
Contact EDITGENE today to design your custom CRISPR model for eukaryotic translation initiation factor 2 complex assembly research.
Frequently Asked Questions About eukaryotic translation initiation factor 2 complex assembly
What is eukaryotic translation initiation factor 2 complex assembly?
It is the biological process (GO:1905143) of assembling the eIF2 heterotrimer from its α, β, and γ subunits, essential for translation initiation.
What genes are involved in eukaryotic translation initiation factor 2 complex assembly?
Key genes include EIF2S1, EIF2S2, EIF2S3, and regulatory kinases such as EIF2AK3 (PERK) [1, 4, 5].
How is eIF2 complex assembly regulated?
It is regulated by the integrated stress response via phosphorylation of eIF2α, and by ER and nutrient stress through the PERK-eIF2α axis [4, 5].
What diseases are linked to eIF2 complex assembly?
Cancer, cardiovascular disease, neurodegeneration, and metabolic disorders have been linked to eIF2 dysregulation [2, 3, 4, 5].
What methods study eIF2 complex assembly?
Ribo-seq, selective translation complex profiling, proteomics, and CRISPR-based genetic models are commonly used [1, 6].
Can CRISPR knockout be used to study eIF2 assembly?
Yes, knockout of EIF2S1, EIF2S2, or EIF2S3 abolishes assembly and reveals subunit essentiality.
What is the role of eIF2α phosphorylation in assembly?
Phosphorylation of eIF2α at S51 regulates the integrated stress response and affects eIF2 complex function.
How does METTL16 relate to eIF2 assembly?
METTL16 has an m6A-independent function in facilitating translation and tumorigenesis, indirectly linking to eIF2-mediated translation.
What is the connection between ALDH2 and eIF2?
ALDH2 interacts with eIF3E to modulate protein translation critical for cardiomyocyte ferroptosis.
Why is eIF2 complex assembly important for cancer research?
Dysregulated translation initiation via eIF2 contributes to tumorigenesis, making it a potential therapeutic target.
Conclusion
GO:1905143 (eukaryotic translation initiation factor 2 complex assembly) is a fundamental biological process that ensures the proper formation of the eIF2 heterotrimer, a key player in translation initiation and cellular stress responses. Its dysregulation is implicated in cancer, cardiovascular disease, neurodegeneration, and metabolic disorders. Continued research using advanced CRISPR models and translation profiling will further elucidate its mechanisms and therapeutic potential.
References
- 1. Vanselow S et al.. 2022. Stepwise assembly of the eukaryotic translation initiation factor 2 complex.. J Biol Chem 298(2):101583 PMID: 35031321
- 2. Su R et al.. 2022. METTL16 exerts an m(6)A-independent function to facilitate translation and tumorigenesis.. Nat Cell Biol 24(2):205-216 PMID: 35145225
- 3. Chen X et al.. 2026. ALDH2/eIF3E Interaction Modulates Protein Translation Critical for Cardiomyocyte Ferroptosis in Acute Myocardial Ischemia Injury.. Circulation 153(3):164-184 PMID: 41111418
- 4. Zhang G et al.. 2021. Integrated Stress Response Couples Mitochondrial Protein Translation With Oxidative Stress Control.. Circulation 144(18):1500-1515 PMID: 34583519
- 5. Balsa E et al.. 2019. ER and Nutrient Stress Promote Assembly of Respiratory Chain Supercomplexes through the PERK-eIF2α Axis.. Mol Cell 74(5):877-890.e6 PMID: 31023583
- 6. Wagner S et al.. 2020. Selective Translation Complex Profiling Reveals Staged Initiation and Co-translational Assembly of Initiation Factor Complexes.. Mol Cell 79(4):546-560.e7 PMID: 32589964
- 7. Itoh Y et al.. 2022. Mechanism of mitoribosomal small subunit biogenesis and preinitiation.. Nature 606(7914):603-608 PMID: 35676484
- 8. Jia J et al.. 2023. Membrane Atg8ylation, stress granule formation, and MTOR regulation during lysosomal damage.. Autophagy 19(6):1893-1895 PMID: 36394332
