NAE1 Human
Description
Role in Neddylation
NAE1 binds to UBA3 to form the NEDD8-activating enzyme (NAE), which initiates neddylation by adenylating NEDD8 and transferring it to E2-conjugating enzymes . This process regulates:
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Cell Cycle Progression: Essential for S/M phase checkpoint control .
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DNA Repair: Facilitates nucleotide excision repair (NER) and non-homologous end joining (NHEJ) by neddylation of CUL4A and Ku proteins .
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Protein Degradation: Modulates ubiquitin-proteasome system activity via cullin-RING ligases .
Disease Associations
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Neurodegeneration: NAE1 interacts with amyloid precursor protein (APP), implicated in Alzheimer’s disease pathogenesis .
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Cancer: Overactivation of neddylation promotes tumor growth; inhibitors like Pevonedistat block NAE1-UBA3 interaction, inducing synthetic lethality in DNA repair-deficient cancers .
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Developmental Disorders: Bi-allelic NAE1 variants cause intellectual disability, ischiopubic hypoplasia, and infection-triggered neurodegeneration .
Functional Studies
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Spermatogenesis: Nae1 knockout in mice causes pachytene-stage arrest in spermatocytes, leading to infertility due to defective homologous recombination .
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Cardiac Hypertrophy: K238 crotonylation of NAE1 enhances gelsolin (GSN) neddylation, stabilizing GSN and promoting pathological cytoskeletal remodeling .
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Myocardial Infarction: RBM15 stabilizes NAE1 mRNA, reducing cardiomyocyte apoptosis; NAE1 inhibition exacerbates cell death .
Genetic Variants
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Four individuals with NAE1 variants exhibited ischiopubic synchondrosis hypoplasia and infection-triggered lymphopenia . Fibroblasts showed 50% reduced NAE1 levels and increased apoptosis under proteasomal stress .
Pharmacological Targeting
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Pevonedistat (MLN4924): Phase III trials for hematologic malignancies target NAE1-UBA3, showing efficacy in disrupting cullin neddylation and inducing cancer cell death .
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NAE-IN-1: Induces apoptosis and G2/M cell cycle arrest by elevating ROS levels .
Research Applications
NAE1 Human Recombinant is utilized for:
Product Specs
Q&A
What is the biological function of NAE1 in humans?
NAE1 (NEDD8-activating enzyme E1 regulatory subunit) is a critical component of the neddylation pathway. Neddylation is a post-translational modification process that conjugates the ubiquitin-like protein NEDD8 to target substrates. This modification regulates the activity, stability, and localization of various proteins, particularly cullin-RING ligases (CRLs), which are essential for protein degradation via the ubiquitin-proteasome system. NAE1 forms a heterodimer with UBA3 (the catalytic subunit) to activate NEDD8 by adenylation, enabling its subsequent transfer to target proteins .
In addition to its canonical role in neddylation, NAE1 has been implicated in other cellular processes such as cell cycle regulation, DNA damage response, and oxidative stress management. Recent studies also highlight its involvement in specialized contexts like spermatogenesis, cardiac development, and immune responses .
How does NAE1 deficiency affect cellular homeostasis?
NAE1 deficiency disrupts neddylation, leading to impaired regulation of CRLs and other neddylated substrates. This dysregulation can result in the accumulation of misfolded or damaged proteins, altered cell cycle progression, and increased susceptibility to stress-induced apoptosis. For example:
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Skeletal Development: In individuals with bi-allelic variants in NAE1, skeletal abnormalities such as ischiopubic hypoplasia have been observed. Transcriptomic analyses revealed downregulation of key developmental genes like RUNX2 and SOX9 .
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Cellular Stress: Under proteasomal stress conditions (e.g., induced by MG132), cells with reduced NAE1 expression exhibit increased apoptosis due to an inability to restore proteasomal function .
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Immune Function: NAE1 deficiency in lymphocytes leads to decreased NF-κB translocation and impaired immune responses during infections .
These findings underscore the importance of NAE1 in maintaining cellular homeostasis under both normal and stress conditions.
What experimental models are available for studying NAE1?
Several experimental models have been developed to investigate the function of NAE1:
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Cell Lines: Human fibroblasts with genetic variants in NAE1 serve as a model for studying its role in cellular stress responses .
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Animal Models: Germ cell-specific Nae1-knockout mice have been used to explore its role in spermatogenesis. These mice exhibit late-pachytene arrest during meiosis and increased apoptosis in spermatocytes .
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Knock-in Mice: Mice carrying mutations that mimic or abolish specific post-translational modifications (e.g., K238 crotonylation) have been employed to study the functional consequences of these modifications on cardiac hypertrophy .
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In Vitro Systems: Lentiviral systems for overexpressing or silencing NAE1 allow researchers to manipulate its expression levels in various cell types .
Each model offers unique advantages depending on the research question being addressed.
How does NAE1-mediated neddylation influence spermatogenesis?
NAE1 plays a crucial role in regulating meiotic recombination during spermatogenesis through its involvement in neddylation. In Nae1-knockout mice:
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Spermatocytes exhibit late-pachytene arrest due to defective double-strand break (DSB) repair.
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Excessive stabilization of recombination intermediates prevents proper crossover formation.
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These defects ultimately lead to increased apoptosis and infertility .
Single-cell transcriptomic analyses further reveal that NAE1 deficiency alters the transcriptional profile of germ cells, highlighting its importance in meiotic progression and germ cell survival.
What are the implications of NAE1 dysregulation in cardiac development?
Neddylation is essential for both embryonic and postnatal cardiac development. Targeted deletion of Nae1 in mouse cardiomyocytes results in:
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Embryonic Effects: Myocardial hypoplasia and ventricular non-compaction, leading to perinatal lethality.
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Postnatal Effects: Disruption of metabolic transitions (from glycolysis to oxidative metabolism), impaired transverse tubule formation, and failure of fetal-to-adult isoform switching. These changes culminate in immature cardiomyocytes and heart failure .
Additionally, K238 crotonylation of NAE1 has been shown to modulate cardiac hypertrophy by influencing gelsolin-mediated cytoskeletal dynamics . These findings suggest that both genetic and post-translational modifications of NAE1 are critical for cardiac health.
How does NAE1 contribute to immune responses against cancer?
NAE1-mediated neddylation is activated during CD8+ T cell activation and is essential for their effector functions. Mechanistically:
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Upregulation of NAE1 enhances mitochondrial fitness and protein dynamics required for T cell proliferation and cytotoxic activity.
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Genetic ablation of NAE1 impairs antitumor immunity by disrupting proteomic balance during T cell activation.
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Overexpression of NAE1 improves the efficacy of adoptive cell transfer therapies targeting tumors .
These findings highlight the potential of targeting NAE1 as a therapeutic strategy in cancer immunotherapy.
What methods are used to study post-translational modifications (PTMs) of NAE1?
The study of PTMs such as crotonylation or phosphorylation on NAE1 involves several advanced methodologies:
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Mass Spectrometry: Tandem mass tag (TMT)-labeled quantitative proteomics is used to identify PTM sites.
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Mutagenesis Studies: Site-directed mutagenesis (e.g., K238R or K238Q mutations) helps elucidate the functional consequences of specific PTMs.
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Co-immunoprecipitation: This technique identifies interacting partners affected by PTMs.
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Functional Assays: Cellular phenotypes such as apoptosis, proliferation, or differentiation are assessed following manipulation of PTM states .
Integrating these approaches provides comprehensive insights into how PTMs regulate NAE1 function.
How can researchers address contradictory data regarding NAE1's role?
Contradictions often arise due to differences in experimental conditions, models used, or data interpretation. To address these discrepancies:
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Standardization: Ensure consistent use of reagents, protocols, and controls across experiments.
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Replication: Validate findings using multiple models (e.g., cell lines vs. animal models).
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Data Integration: Combine transcriptomic, proteomic, and functional data for a holistic understanding.
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Collaborative Efforts: Share resources and data with other research groups working on similar questions.
By adopting these strategies, researchers can reconcile conflicting findings and advance our understanding of NAE1 biology.
What future directions should researchers explore regarding NAE1?
Several unanswered questions provide opportunities for future research:
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Mechanistic Studies: Elucidate how specific PTMs regulate NAE1's interactions with substrates or cofactors.
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Disease Models: Develop models that mimic human diseases associated with NAE1 mutations (e.g., neurodegeneration or lymphopenia).
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Therapeutic Potential: Investigate small molecules or peptides that modulate NAE1 activity for therapeutic purposes.
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Systems Biology Approaches: Use computational modeling to predict the impact of neddylation on cellular networks.
These directions will help uncover novel roles for NAE1 in health and disease.
Product Science Overview
NEDD8 Activating Enzyme E1 Subunit 1, also known as NAE1, is a crucial component in the process of neddylation, a post-translational modification similar to ubiquitination. This enzyme plays a significant role in the regulation of various cellular processes, including cell cycle progression, signal transduction, and protein degradation.
The NAE1 gene is located on chromosome 16q22.1 and encodes a protein that is approximately 59 kDa in size . The protein is composed of 534 amino acids and has several domains that are essential for its function. NAE1 forms a heterodimer with UBA3, another subunit of the NEDD8-activating enzyme, to create the functional E1 enzyme complex .
NAE1 is responsible for the activation of NEDD8, a ubiquitin-like protein. The activation process involves several steps:
- Adenylation: NAE1 first adenylates the C-terminal glycine residue of NEDD8 using ATP.
- Thioester Bond Formation: The adenylated NEDD8 is then linked to the catalytic cysteine residue of UBA3, forming a NEDD8-UBA3 thioester and releasing AMP.
- Transfer to E2 Enzyme: Finally, NEDD8 is transferred to the catalytic cysteine of the E2 enzyme, UBE2M .
This activation process is crucial for the subsequent conjugation of NEDD8 to target proteins, a process known as neddylation. Neddylation regulates the activity of cullin-RING ligases (CRLs), which are involved in the ubiquitin-proteasome system for protein degradation .
