Eukaryotic protein production in designed storage organelles

Area of Science:

• Biotechnology
• Cell Biology
• Protein Engineering

Background:

• Protein bodies (PBs) are plant organelles that store seed storage proteins.
• The Zera domain from maize gamma zein induces PBs in non-seed plant tissues.
• This property offers potential for recombinant protein production.

Purpose of the Study:

• To investigate the ability of the Zera domain to induce protein bodies in non-plant eukaryotic hosts.
• To assess the utility of Zera-induced PBs for recombinant protein accumulation and purification across different cell types.

Main Methods:

• Fusion of Zera with fluorescent and therapeutic proteins.
• Expression of Zera fusion proteins in various eukaryotic systems (tobacco, fungi, mammalian, insect cells).
• Analysis of protein accumulation, localization, and host cell viability.

Main Results:

• Zera fusions successfully formed PB-like organelles in all tested eukaryotic systems.
• Recombinant proteins were insulated within these organelles, enhancing production and stability.
• Induced PBs facilitated efficient recovery and purification of recombinant proteins.

Conclusions:

• The Zera sequence is a universal tool for inducing protein bodies in diverse eukaryotic hosts.
• This cross-kingdom conserved mechanism is valuable for manufacturing non-secreted recombinant proteins.
• Universal ER pathways likely mediate this protein insulation process.