A highly efficient human cell-free translation system.

Area of Science:

• Molecular Biology
• Biochemistry
• Cell Biology

Background:

• Cell-free protein synthesis (CFPS) is crucial for in vitro protein expression across various scientific, industrial, and therapeutic fields.
• Existing in vitro systems face limitations in efficiency and physiological relevance.
• Human translation mechanisms are complex and require robust in vitro models for study.

Approach:

• Developed an optimized human CFPS system using HEK293T cell extracts engineered to express GADD34 and K3L proteins.
• Engineered cells to suppress phosphorylation of the translation initiation factor eIF2α, simplifying lysate preparation.
• Investigated the impact of GADD34 and K3L expression on eIF2α phosphorylation and translation efficiency.

Key Points:

• The engineered CFPS system enhances translation of both 5' cap-dependent and IRES-mediated mRNAs.
• Endogenous expression of GADD34 and K3L maintains low eIF2α phosphorylation in extracts.
• eIF2α phosphorylation increases moderately during in vitro reactions, dependent on GCN2 kinase activity.
• Evidence suggests activation of regulatory pathways like eEF2 phosphorylation and ribosome quality control.

Conclusions:

• The novel human CFPS system provides a highly efficient and simplified platform for in vitro protein synthesis.
• This system enables the study of human translation mechanisms under more physiological conditions outside the cell.
• The optimized system has broad potential applications in scientific research, biotechnology, and therapeutic development.