Inducible translocation trap: a system for detecting inducible nuclear translocation

Area of Science:

• Molecular Biology
• Cell Biology
• Biochemistry

Background:

• Signal transduction pathways involve the movement of proteins within cells.
• Identifying proteins that translocate to the nucleus is crucial for understanding cellular responses.
• Existing methods for tracking nuclear translocation can be limited in scope or throughput.

Purpose of the Study:

• To develop and validate a general system for identifying proteins that translocate into the nucleus upon extracellular stimulation.
• To demonstrate the efficacy of the inducible translocation trap (ITT) system in isolating specific nuclear translocating proteins.

Main Methods:

• Constructed a retroviral cDNA expression library encoding fusion proteins with a LexA DNA binding domain.
• Utilized a reporter gene system with LexA binding sites in the promoter.
• Transduced the library into cell lines and selected cells exhibiting reporter gene expression upon extracellular stimuli via flow-cytometric sorting.
• Validated the system by screening for proteins translocating in response to IFNgamma.

Main Results:

• Successfully developed the inducible translocation trap (ITT) system.
• Identified cDNA encoding Stat1 as a protein that translocates into the nucleus upon IFNgamma stimulation.
• Demonstrated that ITT can isolate nuclear translocating proteins induced by extracellular stimuli.

Conclusions:

• The inducible translocation trap (ITT) is a versatile and effective system for identifying proteins that translocate into the nucleus.
• ITT facilitates the dissection of dynamic translocation processes in various biological contexts.
• This system offers a powerful tool for advancing research in signal transduction and nuclear biology.