Mutant IRS-1 PTB domain proteins, and coding sequence and application thereof

Abstract

Amino acid residues of PTB domain wild-type proteins of IRS-1 are subjected to site-directed mutation, R at a 99th site is mutated to L, S at a 102nd site is mutated to A, a mutant vector is constructed, proteins are expressed and purified, and a PTB fusion protein mutant GST-PTB-R99L / S102A of IRS-1 is expressed in escherichia coli, and the affinity of the mutant specifically binding to tyrosine residue phosphorylated IGF-1R is greatly enhanced. The constructed recombinant plasmid-expressed fusion protein (Arg)9-GST-PTB-MUTANT of the PTB fusion protein mutant of IRS-1 and a cell penetrating peptide (Arg)9 can penetrate and enter cancer cells, replaces an endogenous IRS-1 protein in cancer cells to bind to IGF-1R, blocks multiple signal pathways involved in the endogenous IRS-1 protein, caninhibit the proliferation and invasion of tumor cells, and has significant anti-tumor effect.

Description

technical field [0001] The invention belongs to the field of biotechnology, relates to a protein polypeptide with strong affinity for the phosphorylated tyrosine residue of insulin-like growth factor receptor IGF-1R, relates to gene recombination, bioinformatics prediction, mutant construction and prokaryotic carrier fusion protein expression and purification, especially the application of a PTB-MUTANT fusion gene and its prokaryotic expression vector. Background technique [0002] Overview of phosphorylated tyrosine and its anti-tumor application: anti-tumor drugs mainly include cytotoxic anti-tumor drugs, anti-tumor drugs targeting cell signal transduction molecules, etc. Among them, tyrosine kinase inhibitors can penetrate cell membranes and target To tumor cells has become a hotspot in international new drug research. Phosphorylation modification of protein tyrosine is the basic mechanism to regulate cell signal transduction, and cancerous cells often show abnormally in...

AI Technical Summary

Problems solved by technology

However, the preparation cost of monoclonal antibody is high, the price is expensive, the quality of different batches is unstable, and the molecular weight is large, and the cell penetration ability is poor; kinase inhibitors strongly inhibit the signaling pathways related to pY in cells, and there are certain side effects. A condition in which a genetic mutation leads to drug resistance, thereby losing efficacy of the treatment 2

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