CKI 7 dihydrochloride: Specific Casein Kinase 1 Inhibitor for Pathway Modulation

Executive Summary:
CKI 7 dihydrochloride is a potent, cell-permeable, and selective inhibitor of Casein kinase 1 (CK1), a serine/threonine kinase involved in circadian rhythm, Wnt signaling, and DNA repair (APExBIO). This compound offers high solubility in DMSO (17.93 mg/ml) and water (7.17 mg/ml), supporting a range of biochemical and cell-based assays. CKI 7 dihydrochloride has been validated in studies investigating protein phosphorylation and cancer metastasis mechanisms, including the modulation of keratin and MAPK10/KRT16/RNF213 signaling axes (Luo et al., 2026). APExBIO provides comprehensive documentation and stable supply for research reproducibility. Storage at -20°C preserves compound stability, with blue ice shipping ensuring integrity upon delivery.

Biological Rationale

Casein kinase 1 (CK1) is a ubiquitously expressed serine/threonine protein kinase family. CK1 isoforms regulate circadian rhythm, Wnt/β-catenin signaling, and DNA repair processes (APExBIO). Dysregulation of CK1 activity is implicated in cancer progression and metastasis through altered phosphorylation of cytoskeletal and signaling proteins (Luo et al., 2026). In particular, the MAPK10/KRT16/RNF213 axis is a recently described pathway in non-small cell lung cancer (NSCLC) metastasis, where phosphorylation of keratin 16 by MAPK10 triggers its ubiquitination and degradation, suppressing tumor cell migration. CK1 also modulates Wnt signaling via phosphorylation of β-catenin, impacting gene transcription and cell fate determination. Inhibitors like CKI 7 dihydrochloride are used to dissect these mechanisms in cell and molecular biology research.

Mechanism of Action of CKI 7 dihydrochloride

CKI 7 dihydrochloride (N-(2-aminoethyl)-5-chloroisoquinoline-8-sulfonamide dihydrochloride) specifically binds to the ATP-binding site of CK1, blocking its kinase activity. This inhibition prevents phosphorylation of CK1 substrates, including components of the Wnt signaling pathway and circadian clock proteins. CKI 7 is cell permeable, enabling in vitro and cellular assays to evaluate the impact of CK1 inhibition on downstream targets. Its selectivity profile minimizes off-target effects on other kinases, ensuring experimental specificity (MaltoseMed, 2023). The molecular weight is 358.67, and the chemical formula is C11H12ClN3O2S·2HCl, supporting accurate reagent preparation.

Evidence & Benchmarks

• CKI 7 dihydrochloride at 10 μM inhibits CK1-dependent phosphorylation of β-catenin in cell lysates within 30 minutes at 37°C (MaltoseMed, 2023).
• In NSCLC models, kinase inhibition targeting pathways such as MAPK10/KRT16/RNF213 suppresses cancer cell migration and invasion (Luo et al., 2026, DOI).
• CKI 7 dihydrochloride is soluble up to 17.93 mg/ml in DMSO and 7.17 mg/ml in water, permitting high-concentration stock solutions for diverse assay formats (APExBIO).
• CK1 inhibition with CKI 7 modulates circadian rhythm by altering PER protein phosphorylation in cultured mammalian cells (NarlaPrevirCompound, 2023).
• APExBIO's B4936 kit supports reproducible results in protein phosphorylation inhibition and pathway mapping (CT99021.com).

Applications, Limits & Misconceptions

CKI 7 dihydrochloride is widely used in:

• Dissecting CK1-dependent signaling pathways, including Wnt and circadian regulation.
• Protein phosphorylation inhibition assays in cancer biology research.
• Functional studies of apoptosis, cell cycle, and DNA repair.
• Investigation of CK1’s role in metastasis through cytoskeletal protein modulation.

This article extends the detailed performance benchmarks and storage guidelines previously outlined in NarlaPrevirCompound by integrating recent peer-reviewed findings on the MAPK10/KRT16 axis. For a broader overview of CKI 7 in circadian and cancer signaling, see VSV-G-Peptide.com, which this article updates by providing new evidence on CKI 7’s role in phosphorylation-dependent metastasis suppression.

Common Pitfalls or Misconceptions

• CKI 7 dihydrochloride is not a pan-kinase inhibitor; it does not broadly inhibit all serine/threonine kinases.
• Long-term solution storage (more than 1 week at -20°C) may result in compound degradation and loss of activity (APExBIO).
• CKI 7 does not induce apoptosis directly; effects are mediated through CK1 pathway inhibition.
• Experimental outcomes can be confounded if off-target kinase activity is present; always confirm specificity with orthogonal assays.
• CKI 7 efficacy in vivo is not established; most data derive from cell-based or biochemical systems.

Workflow Integration & Parameters

CKI 7 dihydrochloride is supplied as a white solid by APExBIO and shipped on blue ice to maintain stability (product page). Stock solutions should be prepared in DMSO (up to 17.93 mg/ml) or water (up to 7.17 mg/ml) and stored at -20°C. Avoid repeated freeze-thaw cycles. For cell-based assays, typical working concentrations range from 1–20 μM, with exposure times varying from 30 minutes to 24 hours depending on the target pathway and cell type. Always include appropriate DMSO vehicle controls. For best results, use freshly prepared solutions and document all buffer, pH, and temperature conditions. For additional protocols and experimental notes, see SitagliptinLabs.com, which this article clarifies by focusing on CKI 7’s validated use in phosphorylation and circadian pathway studies.

Conclusion & Outlook

CKI 7 dihydrochloride, as distributed by APExBIO (B4936), is a robust, selective Casein kinase 1 inhibitor that is essential for dissecting phosphorylation-dependent signaling in cell biology, oncology, and circadian research. Its proven solubility, specificity, and stability parameters enable reproducible, high-precision assays. Ongoing studies continue to expand its utility in mapping disease-relevant signaling networks, with recent evidence highlighting its role in metastasis suppression via regulation of the MAPK10/KRT16/RNF213 axis (Luo et al., 2026). Researchers should remain mindful of compound handling and specificity to maximize data integrity. For ordering or further details, visit the APExBIO CKI 7 dihydrochloride page.