Shedding Light on the Ghost Proteome

Area of Science:

• Molecular Biology
• Proteomics
• Genomics

Background:

• Eukaryotic messenger RNAs (mRNAs) were traditionally considered monocistronic, encoding only one protein.
• Recent large-scale proteomics studies reveal proteins translated from alternative open reading frames (AltORFs) within mRNAs.
• These alternative proteins, part of the 'Ghost proteome', were previously overlooked and are absent from conventional protein databases.

Purpose of the Study:

• To review the emerging understanding of the 'Ghost proteome' derived from alternative open reading frames (AltORFs).
• To highlight the functional significance and implications of these alternative proteins in biological processes.
• To discuss the potential of the Ghost proteome in identifying novel biomarkers and therapeutic targets.

Main Methods:

• Literature review of recent proteomics and genomics studies.
• Analysis of data identifying alternative open reading frames (AltORFs) in eukaryotic mRNAs.
• Synthesis of evidence regarding the functional roles of the 'Ghost proteome'.

Main Results:

• Identification of a significant 'Ghost proteome' translated from alternative open reading frames (AltORFs).
• Growing evidence supports the functional roles of these alternative proteins in physiological and physiopathological conditions.
• The Ghost proteome offers new insights into cellular signaling pathways.

Conclusions:

• The 'Ghost proteome' represents a significant expansion of the known proteome, challenging the monocistronic mRNA paradigm.
• Alternative proteins encoded by AltORFs are implicated in fundamental biological functions and disease states.
• Understanding the Ghost proteome opens avenues for novel diagnostic markers and therapeutic strategies.