IGF-1 LR3

IGF-1 LR3 Overview

IGF-1 LR3 is an 83-amino acid synthetic polypeptide engineered to overcome limitations of native IGF-1 through two strategic modifications: glutamic acid-to-arginine substitution at position 3 and addition of a 13-residue N-terminal extension (MFPAMPLSSLFVN). These alterations reduce binding affinity for IGFBPs by approximately 100-fold while maintaining full target receptor activation capacity, resulting in increased bioavailability and extended half-life compared to native IGF-1. Research models examine its activation of tyrosine kinase signaling, downstream PI3K-Akt and Ras-MAPK pathways, effects on substrate uptake in experimental models, protein synthesis stimulation, and molecular proliferation in laboratory settings. Francis et al. (1992).

Castellino et al. (1992).

History

IGF-1 LR3 is an engineered analogue of human insulin-like growth factor 1, developed for laboratory use during work on cell culture supplementation in the 1990s. It differs from native IGF-1 in two respects: an arginine substitution at position 3, and a thirteen-residue extension at the N-terminus. Both modifications sharply reduce its association with the IGF-binding proteins that otherwise sequester the native peptide, which made it useful as a research reagent where a predictable free concentration matters. It is widely used in cell culture research and is not a naturally occurring sequence.

IGF-1 LR3 Structure

CAS #:

946870-92-4