Research Overview
Why the binding proteins matter
Receptor signalling
LR3 is studied as an agonist at the IGF-1 receptor, a receptor tyrosine kinase that autophosphorylates and recruits IRS-1 and Shc adaptors. Downstream, work focuses on the PI3K–Akt–mTOR axis associated with protein synthesis and survival, and the Ras–MAPK arm associated with proliferation. Cross-reactivity with the insulin receptor and hybrid receptors is a standard control consideration in these experiments.
Applications in culture and bioprocess
- Serum-free and reduced-serum media formulations, where LR3 substitutes for insulin or serum growth factors in CHO and hybridoma production systems
- Myoblast and satellite cell studies examining differentiation, hypertrophy signalling and myotube formation in vitro
- Comparative assays against native IGF-1 and IGF-1 DES(1-3) to separate binding-protein effects from receptor-level potency
Handling as a protein, not a peptide
At 83 residues with multiple disulfide bonds, LR3 behaves like a small protein: it adsorbs to plastic and glass at low concentration, is sensitive to freeze–thaw, and is commonly reconstituted with a carrier such as 0.1% bovine serum albumin for dilute working stocks. All described use is laboratory research; none of it concerns human application.
