ABI1 Antibody
Product Specs
Target Background
ABI1 (Abl interactor 1) is implicated in the negative regulation of cell growth and transformation through interactions with non-receptor tyrosine kinases ABL1 and/or ABL2. It plays a role in regulating EGF-induced Erk pathway activation, cytoskeletal reorganization, and EGFR signaling. ABI1, in conjunction with EPS8, participates in Ras-to-Rac signal transduction. In vitro studies demonstrate that a trimeric complex of ABI1, EPS8, and SOS1 exhibits Rac-specific guanine nucleotide exchange factor (GEF) activity, with ABI1 acting as an adapter. ABI1 also regulates ABL1/c-Abl-mediated phosphorylation of ENAH and recruits WASF1 to lamellipodia, potentially regulating WASF1 protein levels. In the brain, ABI1 appears to regulate dendritic outgrowth and branching, influencing the shape and number of synaptic contacts in developing neurons.
Extensive research highlights ABI1's multifaceted roles in various cancers:
- Oncogenic Role in Hepatocellular Carcinoma (HCC): ABI1 contributes to HCC development and progression, serving as a potential prognostic marker. (PMID: 28339046)
- Role in Hepatitis C Virus (HCV) Propagation: HCV utilizes host Abi1 protein via NS5A to modulate the MEK/ERK signaling pathway, facilitating viral replication. (PMID: 27551040)
- Tumor-Promoting Gene in Epithelial Ovarian Cancer: Abi1 acts as a tumor-promoting gene, correlating with unfavorable prognosis. (PMID: 26193797)
- Drug Resistance in Leukemia: The alpha4-Abi-1 signaling pathway may mediate drug resistance in leukemic cells. (PMID: 24699303)
- Invasive Properties of Colorectal Cancer: Phosphorylated Abi1 contributes to the invasive properties of colorectal cancer. (PMID: 24913355)
- Localization in Colorectal Carcinomas: Abi1 is expressed at the invasive front of colorectal carcinomas and localizes to lamellipodia in cultured colorectal carcinoma cells. (PMID: 24196611)
- Regulation of c-Abl Activation: Abi1 is activated by the c-Abl-Crk-associated substrate (CAS) pathway and reciprocally controls c-Abl activation. (PMID: 23740246)
- Early KRAS Mutation Marker: Abi1 may serve as a marker for early KRAS mutation in hyperplastic polyps. (PMID: 22808230)
- Breast Cancer Recurrence and Survival: High Abi1 expression in breast tumors correlates with early recurrence and worse survival. (PMID: 21046228)
- Role in Gastric Cancer Progression: Downregulation of E3B1/ABI-1 in human carcinomas is associated with tumor progression and prognosis. (PMID: 22430194)
- Regulation of VASP and Leukemic Cell Adhesion: The Abi-1-mediated phosphorylation/dephosphorylation cycle of VASP regulates VASP association with focal adhesions and Bcr-Abl-transformed leukemic cell adhesion. (PMID: 22014333)
- CDK1-mediated Phosphorylation and F-actin Assembly: CDK1-mediated Abi1 phosphorylation attenuates Bcr-Abl-induced F-actin assembly and WAVE complex tyrosine phosphorylation during mitosis. (PMID: 21900237)
- Upregulation in Hepatocellular Carcinoma: Abi1 expression is upregulated in hepatocellular carcinoma tissues and correlates with tumor characteristics and prognosis. (PMID: 20137729)
- Abi-1 Binding to c-Abl: Phosphorylation sites Y398 and Y213 are critical for Abi-1 binding to c-Abl. (PMID: 21320496)
- Ovarian Cancer Metastasis: The integrity of the SOS1/EPS8/ABI1 tri-complex influences ovarian cancer metastasis. (PMID: 21118970)
- Role in Gastric Cancer Progression and Prognosis: Downregulation of ABI1 in human gastric carcinoma is linked to tumor progression and patient prognosis. (PMID: 19554484)
- Regulation of Macropinocytosis: Interactions between Abi1 pY213 and the C-terminal SH2 domain of p85 link Abl kinase signaling to p85-dependent regulation of macropinocytosis. (PMID: 20598684)
- Differential Regulation of Macropinocytosis by Abi1 Isoforms: Abi1 isoforms differentially regulate macropinocytosis based on their affinities for activated Rac1 in the Wave 2 complex. (PMID: 20479892)
- Inhibition of Cell Proliferation: ABI1 downregulation is observed in gastric cancer cells; ABI1 overexpression inhibits cell proliferation. (PMID: 20193272)
- Abi-1 and VASP Interaction in Human Platelets: Analysis of protein-protein interactions between Abi-1 and VASP in human platelets. (PMID: 20110575)
- Association with Congenital Acute Monocytic Leukemia: The t(10;11)(p11.2;q23) translocation involving MLL and ABI1 is associated with congenital acute monocytic leukemia. (PMID: 12547160)
- Regulation of c-Abl-mediated Mena Phosphorylation: Abi-1 regulates c-Abl-mediated Mena phosphorylation. (PMID: 12672821)
- Regulation of WAVE2 Actin Polymerization Activity: Abi1 interacts with WAVE2, enhancing its actin polymerization activity and mediating the assembly of a WAVE2-Abi1-Nap1-PIR121 complex. (PMID: 15048123)
- Regulation of Cdc2 Kinase: Abi enhances Abl-mediated downregulation and phosphorylation of Cdc2 kinase. (PMID: 15591787)
- Role in Abl-evoked WAVE2 Phosphorylation: Abi-1 links c-Abl and WAVE2, promoting Abl-evoked WAVE2 tyrosine phosphorylation necessary for linking WAVE2 to activated Rac and actin remodeling. (PMID: 15657136)
- Role in Listeria Entry and Membrane Ruffling: Abi1 is recruited to the entry site during Listeria entry and InlB-induced membrane ruffling. (PMID: 15769844)
- Coordination of Kinase-Substrate Interactions: Abi-1 promotes Abl-mediated BCAP phosphorylation and coordinates kinase-substrate interactions. (PMID: 15893754)
- Regulation of Rac1 Activation: E3B1 overexpression sensitizes EGF-induced Rac1 activation. (PMID: 16182283)
- Regulation of Actin Nucleator Localization/Activity: The Eps8/Abi1 complex may regulate actin nucleator localization and/or activity. (PMID: 16225669)
- Role in c-Abl-mediated WAVE2 Activation and Actin Remodeling: c-Abl activates WAVE2 via tyrosine phosphorylation to promote actin remodeling, with Abi-1 acting as a crucial link. (PMID: 16899465)
- Role of Abi-3 (NESH) in c-Abl Regulation: Abi-3 is a component of the Abi/WAVE complex, likely playing a distinct role in c-Abl regulation. (PMID: 17101133)
- Role in Chlamydia trachomatis Invasion: Chlamydia trachomatis activates Rac and promotes its interaction with WAVE2 and Abi-1 to induce actin cytoskeletal rearrangements needed for invasion. (PMID: 17501982)
- Role of Abi1 in Breast Cancer Spread: ABI1's role in breast cancer spread may be mediated via the phosphatidylinositol 3-kinase pathway. (PMID: 17951403)
- c-Abl Kinase Inhibition: c-Abl kinase inhibition is mediated by a phosphotyrosine located in trans in the c-Abl substrate, Abi1. (PMID: 18328268)
- Role in Cell-Cell Junction Formation and Stability: An Abi/Dia complex is required for cell-cell junction formation and stability. (PMID: 19158278)
- Regulation of Src-Id1-MMP9 Axis in Breast Cancer: Abl interactor 1 regulates the Src-Id1-matrix metalloproteinase 9 axis and is essential for invadopodia formation, extracellular matrix degradation, and breast cancer cell growth. (PMID: 19843640)
- SSH3BP1 as a Regulator of Macropinocytosis: Human SSH3BP1 is a marker of macropinocytic vesicles and potential regulator of macropinocytosis, potentially involved in vesicle fusion. (PMID: 11034908)
Q&A
Here’s a structured FAQ collection for ABI1 antibody research, organized by scientific depth and methodological focus:
How to validate ABI1 antibody specificity in Western blotting?
Methodology:
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Use reducing conditions (30 µg lysate, 5–20% SDS-PAGE, 70–90V separation) and transfer to nitrocellulose membranes .
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Optimize blocking (5% non-fat milk/TBS, 1.5 hours) and primary antibody concentration (0.5 µg/mL overnight at 4°C) .
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Validate using knockdown/knockout cell lines or competitive peptides. Discrepancies in observed vs. expected molecular weight (e.g., 60–65 kDa vs. 55 kDa ) may indicate post-translational modifications or splice variants.
What are common applications for ABI1 antibodies in cell biology?
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Immunofluorescence: Paraffin-embedded tissue sections (5 µg/mL primary antibody, Cy3/DAPI counterstaining) .
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Flow cytometry: Fixation with 4% paraformaldehyde, permeabilization, and 10% goat serum blocking .
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Functional studies: Investigate ABI1’s role in actin dynamics, EGFR signaling, or dendritic outgrowth .
How to troubleshoot non-specific bands in ABI1 Western blots?
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Compare antibody performance across species (human, mouse, rat) .
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Pre-adsorb antibodies with excess immunogen peptide.
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Validate using orthogonal methods (e.g., co-immunoprecipitation with known interactors like WAVE2 or SOS1 ).
How does ABI1 phosphorylation affect antibody binding in cancer models?
Key mechanism:
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CDK1/cyclin B-mediated phosphorylation at Ser-216/218 disrupts ABI1’s interaction with WAVE2, reducing Bcr-Abl-induced actin polymerization .
Experimental design:
What regulatory mechanisms influence ABI1 stability in ABA signaling?
Findings:
How to resolve conflicting data on ABI1’s role in EGFR vs. Ras/Rac pathways?
Analysis framework:
| Pathway | ABI1 Function | Experimental Model | Citation |
|---|---|---|---|
| EGFR signaling | Inhibits Erk activation | Breast cancer tissue | |
| Ras/Rac cascade | Forms trimeric GEF complex with EPS8 | In vitro reconstitution |
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Context-dependent interactions (e.g., tissue type, post-translational state) may explain discrepancies.
How to study ABI1-protein interactions in live cells?
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Firefly luciferase complementation imaging: Transiently express ABI1 and PUB12/13 in N. benthamiana leaves .
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Co-IP optimization: Use mild detergents (e.g., 1% NP-40) to preserve complexes like ABI1-EPS8-SOS1 .
What controls are essential for ABI1 antibody-based assays?
| Assay Type | Positive Control | Negative Control |
|---|---|---|
| IHC | ABI1-overexpressing cell pellets | ABI1 siRNA-treated tissue |
| Flow cytometry | MCF-7 cells (high ABI1 expression) | Isotype-matched IgG |
