Carbonic Anhydrase 3 Overexpression Modulates Signalling Pathways Associated with Cellular Stress Resilience and...

Area of Science:

• Biochemistry
• Cell Biology
• Molecular Biology

Background:

• Carbonic anhydrase 3 (CA3) has low enzymatic activity but unique surface cysteines susceptible to oxidative stress.
• CA3 is highly expressed in muscle and linked to cellular protection, notably via interactions with BAG3 and modulation of autophagy.
• Previous studies suggest CA3 overexpression protects cardiomyocytes from hypoxia-induced apoptosis.

Purpose of the Study:

• To investigate the impact of CA3 overexpression on cellular pathways and protein interactions.
• To identify novel CA3 binding partners and understand CA3's non-enzymatic functions.
• To explore CA3's role in cellular stress response mechanisms.

Main Methods:

• RNA sequencing and proteomics were employed to analyze cellular changes in HEK293T, MDA-MB-231, and SVCT cells.
• Gene Set Enrichment Analysis (GSEA) was performed on RNA sequencing data.
• HaloTag pull-down experiments followed by mass spectrometry were used for proteomic analysis.

Main Results:

• CA3 overexpression led to the down-regulation of pathways involved in protein synthesis, RNA processing, and neurodegenerative disease signaling in HEK293T cells.
• Similar pathway down-regulation was observed in breast epithelial cells, with hypoxia additionally suppressing interferon signaling.
• Proteomics identified heat shock proteins and ribosomal protein S2 as potential CA3 binding partners, and RANBP2 was consistently upregulated.

Conclusions:

• CA3 modulates key cellular processes, including protein synthesis and signaling, independent of its enzymatic activity.
• CA3 contributes to cellular stress resilience through pathway regulation and protein interactions.
• Findings suggest CA3's involvement in autophagy and neurodegenerative disease pathways warrants further investigation.