What Is the Molecular Structure of IGF-1 LR3?

Native IGF-1 is a compact, 70-amino-acid single-chain polypeptide folded by three internal disulfide bonds into a structure similar to proinsulin. IGF-1 LR3 keeps that same core folded structure but adds a 13-residue extension to the N-terminal end of the chain, bringing the total residue count to 83, and replaces the glutamic acid normally found at position 3 with arginine.

Neither modification changes the region of the molecule that binds the IGF-1 receptor, which is why IGF-1 LR3 retains receptor-binding activity comparable to native IGF-1 in published in-vitro research. What the structural changes do alter is the molecule's surface chemistry near the N-terminus, which is the region primarily responsible for binding to IGF-binding proteins (IGFBPs) in circulation.

This structural summary reflects general, well-established peptide chemistry and is provided for research-education purposes only. REVIVE LAB UAE does not sell IGF-1 LR3, does not synthesize or test it, and this page is not an invitation to purchase — it exists purely to describe the compound's known structure for researchers who encounter the name in the literature.