Protein evolution by hypermutation and selection in the B cell line DT40.

Area of Science:

• Evolutionary biology
• Molecular biology
• Immunology

Background:

• Natural evolution relies on genome-wide mutations and selection.
• Antibody affinity maturation involves immunoglobulin gene hypermutation and B cell selection.
• Simulating protein evolution in culture requires combining hypermutation with selection.

Purpose of the Study:

• To optimize a GFP transgene in DT40 cells through artificial evolution.
• To demonstrate the feasibility of combining hypermutation with selection for protein evolution in cell culture.

Main Methods:

• Utilized hypermutation of a GFP transgene in the DT40 B cell line.
• Employed iterative fluorescence-activated cell sorting for selection of beneficial mutations.
• Applied principles of artificial evolution to protein engineering.

Main Results:

• Successfully optimized the GFP transgene through iterative rounds of hypermutation and sorting.
• Demonstrated that artificial evolution can be achieved in a B cell line.
• Showcased the potential for adapting this method to other transgenes.

Conclusions:

• Artificial evolution in DT40 cells provides a powerful platform for protein optimization.
• This method effectively combines gene hypermutation with a selection strategy.
• The approach is adaptable for evolving other transgenes where selection is feasible.