Fyn Lipidation Tag Enables TMC1/2 Cell Surface Expression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The functional expression of TMC1/2 proteins in heterologous cells is challenging due to their trapping in the endoplasmic reticulum, limiting the study of their role as pore-forming subunits of the mechanotransduction channel.
Innovation Solution
A novel method involving the addition of a Fyn lipidation tag to the N-terminus of TMC1/2 proteins promotes their expression on the cell surface, facilitating their functional and structural study and drug screening applications.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If TMC1/2 proteins are expressed in heterologous cells, then the functional study of pore-forming subunits is enabled, but the proteins get trapped in the endoplasmic reticulum and fail to reach the cell surface
Solution Approach 1:
The patent introduces an N-terminal signal peptide sequence as an intermediary element that mediates the transport of TMC1/2 proteins from the endoplasmic reticulum to the cell surface. This signal peptide acts as a temporary guide that facilitates proper localization without being part of the final functional channel structure.
Solution Approach 2:
The patent modifies the N-terminus of TMC1/2 proteins by adding specific signal peptide sequences, changing the protein's localization parameters. This modification alters the trafficking behavior of the protein, enabling it to reach the cell surface while maintaining its pore-forming function.
2Measurement precision
If truncated TMC1/2 proteins are reconstituted in liposomes, then channel formation can be observed, but the technique cannot be scaled up for drug screening
Solution Approach 1:
The patent enables TMC1/2 proteins to autonomously form functional channels in the plasma membrane of heterologous cells without requiring manual liposome reconstitution. The proteins self-organize into functional channels in their native cellular environment, eliminating the need for complex in vitro reconstitution procedures.
Solution Approach 2:
The patent replaces the mechanical liposome reconstitution process with a biological expression system where proteins are directly expressed in heterologous cells. This substitution transitions from an in vitro mechanical assembly approach to an in vivo biological self-organization approach, enabling high-throughput applications.
3Stability of the object's composition
If full-length TMC1/2 proteins are used, then the native channel structure is preserved, but expression in heterologous cells remains challenging
Solution Approach 1:
The patent applies preliminary modifications to the full-length TMC1/2 proteins by adding N-terminal signal peptides before expression in heterologous cells. This preliminary action ensures proper cellular localization and functional expression of the complete native channel structure, avoiding the need for truncation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The Fyn-mTMC1/2 channel is successfully expressed on the cell surface, enabling robust mechanosensitive channel activity, biophysical, and pharmacological property recapitulation of the MT channel, and high-throughput drug screening.
Implementation Method 1
the membrane-anchoring motif provides a signal for myristoylation and palmitoylation
Implementation Method 2
the membrane-anchoring motif provides a signal for myristoylation and palmitoylation
Data Source
AI summary
The subject invention pertains methods for the ectopic expression of a transmembrane protein lacking plasma membrane expression in a heterologous cell line. In embodiments, transmembrane proteins Fyn-TMC1 and/or Fyn-TMC2 are fused to a membrane-anchoring motif, a Fyn lipidation tag, which provides a signal for myristoylation and palmitoylation, allowing further research on these proteins, including but not limited to their function, structure, and drug screening.