Generation and quantitative proteomics analysis of CK2α/α'^(-/-) cells

Area of Science:

• Cellular Biology
• Biochemistry
• Molecular Oncology

Background:

• Protein kinase CK2 (CK2) is a constitutively active enzyme implicated in malignancy.
• High CK2 levels are linked to cancer cell survival by inhibiting apoptosis.
• Understanding CK2's role is crucial for developing targeted cancer therapies.

Purpose of the Study:

• To investigate the druggability of CK2.
• To dissect CK2-dependent cellular processes in neoplasia.
• To generate CK2 subunit-deficient cell models using CRISPR/Cas9.

Main Methods:

• CRISPR/Cas9 genome editing to create CK2 subunit knockout clones.
• Analysis of subunit interactions and degradation pathways.
• Quantitative proteomics to profile protein expression changes.
• Functional analysis of altered cellular pathways.

Main Results:

• Complete suppression of CK2 catalytic subunits (α/α') caused accelerated proteasomal degradation of the β-subunit.
• Quantitative proteomics identified 240 proteins with altered levels (>50%) in CK2α/α' knockout cells.
• Up- and down-regulated proteins were segregated into distinct cellular compartments and functional groups, indicating global cellular rewiring.

Conclusions:

• The catalytic subunits of CK2 are essential for the stability of its regulatory subunit.
• Loss of CK2 catalytic activity induces a profound cellular reorganization to compensate for its absence.
• These findings provide a foundation for understanding CK2's role in cancer and its potential as a therapeutic target.