CNKSR1 Antibody
Description
Introduction to CNKSR1 Antibody
CNKSR1 (Connector Enhancer of Kinase Suppressor of Ras 1) antibodies are specialized tools used to detect and study the CNKSR1 protein, a scaffold protein critical for regulating receptor tyrosine kinase (RTK) signaling pathways . This protein contains PDZ, PH, and SAM domains that mediate interactions with signaling molecules like RhoB-GTP and PTPRH, influencing EGFR/HER2 phosphorylation and cancer progression . CNKSR1 antibodies enable researchers to investigate its roles in cellular signaling, cancer biology, and immune microenvironment modulation .
Recommended Dilutions
| Application | Dilution Range |
|---|---|
| Western Blot (WB) | 1:500–1:1000 |
| Immunoprecipitation (IP) | 0.5–4.0 µg per 1.0–3.0 mg lysate |
| Immunohistochemistry (IHC) | 1:50–1:500 |
| Immunofluorescence (IF) | 1:100–1:500 |
Note: Optimal dilutions may vary by experimental setup; titration is recommended .
Research Applications and Findings
CNKSR1 antibodies have been pivotal in advancing studies across oncology and cell signaling:
Key Research Insights
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EGFR/HER2 Regulation: CNKSR1 scaffolds PTPRH phosphatase to modulate EGFR activity. Antibody-based assays confirmed CNKSR1 colocalizes with RhoB-GTP at the plasma membrane in CUL3/KCTD10-depleted cells, enhancing EGFR signaling in cancers like breast cancer (SKBR-3 cells) .
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Immunotherapy Biomarker: High CNKSR1 expression correlates with "cold" tumor microenvironments in lung adenocarcinoma (LUAD), characterized by low PD-L1 levels and reduced CD8+ T-cell infiltration. IHC validation using CNKSR1 antibodies revealed mutually exclusive expression with PD-L1 in LUAD tissues .
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Neurological Implications: CNKSR1 knockdown models linked the protein to intellectual disability and schizophrenia risk, highlighting its role in neuronal signaling pathways .
Validation Data from Peer-Reviewed Studies
CNKSR1 antibodies have been rigorously validated:
Experimental Validation
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Western Blot: Detected endogenous CNKSR1 in HT-29 cells (human colorectal adenocarcinoma) and human brain tissue .
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Immunohistochemistry: Confirmed overexpression in pancreatic cancer tissues using antigen retrieval with TE buffer (pH 9.0) .
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Immunofluorescence: Localized CNKSR1 to membrane ruffles and the cytosol in SKBR-3 cells, with plasma membrane accumulation upon RhoB-GTP stabilization .
Cross-Reactivity
Clinical and Therapeutic Implications
CNKSR1 antibodies are driving translational research:
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Diagnostic Potential: CNKSR1 overexpression in LUAD tissues (vs. normal) positions it as a biomarker for immunotherapy-resistant tumors .
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Therapeutic Targeting: Disrupting CNKSR1-RhoB-GTP interactions could reactivate EGFR phosphatases, offering a strategy to inhibit oncogenic signaling .
Protocols and Best Practices
For reproducible results:
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WB Protocol: Use RIPA buffer for lysate preparation, resolve 50 µg protein on 8% SDS-PAGE, and transfer to PVDF membranes .
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IHC Protocol: Antigen retrieval with TE buffer (pH 9.0) followed by blocking in 5% BSA .
Limitations and Future Directions
Product Specs
Target Background
- CNKSR1 expression is elevated in pancreatic cancer specimens and has been identified as an independent prognostic marker for overall survival. PMID: 28732488
- Research indicates that connector enhancer of kinase suppressor of Ras 1 protein (CNK1) serves as a molecular platform regulating c-Raf protein (RAF) and c-Akt protein (AKT) signaling, ultimately determining cell fate decisions in a cell type- and cell stage-dependent manner. PMID: 27901111
- Findings reveal that SAM domain-dependent oligomerization by AKT acts as a switch for CNK1 activation. PMID: 27769899
- Tyrosine phosphorylation plays a crucial role in controlling the subcellular localization of CNK1 and its distinct biological functions. PMID: 26319181
- CNK1 mediates ephrinB1 signaling, promoting cell migration through RhoA and JNK activity. PMID: 24825906
- Studies suggest that CNK1-driven proliferation depends on Akt-dependent phosphorylation and inactivation of FoxO proteins. PMID: 21320536
- These findings identify CNK1 as a novel positive regulator of insulin signaling. PMID: 20634316
- Therefore, CNK1 is a key mediator of an oncogenic pathway involved in the invasion of breast and cervical cancer cells, making it a potential target for cancer therapy. PMID: 20197385
- CNK1 promotes oncogenic signaling through Akt in breast cancer cell lines and tumors. PMID: 20383191
- hCNK1 interacts with Rhophilin and RalGDS, Rho and Ras effector molecules respectively, suggesting its role as a scaffold protein mediating crosstalk between the two pathways. PMID: 14749388
- Data demonstrate that the connector enhancer of KSR 1 scaffold protein, through its binding to a RASSF1A/MST1 complex, participates in the proapoptotic signaling initiated by active Ras. PMID: 15075335
- CNK1 couples a subset of Rho exchange factors to the activation of the JNK MAP kinase pathway, and signaling specificity is achieved through complexes containing both upstream activators and downstream targets of Rho. PMID: 15753034
- CNK1 facilitates crosstalk between Src and Raf-1 and is essential for the complete activation of Raf-1. PMID: 15845549
- CNK1 binds through the sterile alpha motif (SAM) and the conserved region in CNK (CRIC) to the AT2 receptor. CNK1 may play a role in the AT2 receptor-mediated signaling pathways. PMID: 16289034
- DC-SIGN was constitutively associated with a signalosome complex composed of the scaffold proteins LSP1, KSR1, and CNK, along with the kinase Raf-1. PMID: 19718030
