Bacteria-to-Human Protein Networks Reveal Origins of Endogenous DNA Damage

Area of Science:

• Molecular Biology
• Genetics
• Cancer Research

Background:

• DNA damage is a known cause of mutations and cancer.
• The internal triggers of endogenous DNA damage remain largely unknown.
• Identifying these triggers is crucial for understanding cancer development.

Purpose of the Study:

• To identify proteins that intrinsically cause DNA damage when overproduced.
• To investigate the mechanisms and network of these DNA damage-promoting proteins.
• To explore the role of these proteins and their human homologs in cancer.

Main Methods:

• Proteomic screening in Escherichia coli to identify DNA damage-up proteins (DDPs).
• Functional clustering and mechanistic studies of DDPs in bacteria.
• Analysis of human homologs of DDPs in cancer databases and tumor samples.
• Experimental validation of DDP function in human cells.

Main Results:

• A large network of DDPs was identified in E. coli, categorized into six functional clusters.
• Mechanisms include reactive oxygen increase, chromosome loss, and replication stalling.
• Human homologs of DDPs are enriched in cancer drivers and associated with poor prognosis.
• Overproduction of human DDP homologs induces DNA damage and mutations in human cells.

Conclusions:

• DNA damage-up proteins (DDPs) are intrinsic instigators of endogenous DNA damage.
• DDPs and their homologs represent a significant network implicated in cancer development.
• These findings reveal potential new cancer drivers and therapeutic targets.