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5-Amino-1MQ
50 mg
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IGF-1 LR3 (Long Arg3 IGF-1) is an 83-amino-acid analogue of insulin-like growth factor 1, supplied as a 1mg lyophilized research peptide. It is studied in IGF-1 receptor signalling, cell growth and protein-synthesis research, and is widely used in cell culture.
IGF-1 LR3 is a modified form of human insulin-like growth factor 1 (IGF-1). It differs from the native 70-amino-acid hormone in two ways: arginine replaces glutamic acid at position 3 (the "R3"), and a 13-amino-acid extension is added to the N-terminus (the "long"), giving a peptide of 83 amino acids.
These changes greatly reduce its binding to IGF-binding proteins (IGFBPs), which normally hold most native IGF-1 in an inactive reserve. As a result, IGF-1 LR3 remains more available to the receptor and is more potent than native IGF-1 in many experimental systems.
IGF-1 LR3 binds and activates the IGF-1 receptor, a receptor tyrosine kinase. Receptor activation triggers the PI3K–Akt–mTOR pathway, associated with protein synthesis and cell survival, and the MAPK/ERK pathway, associated with cell proliferation and differentiation.
Because it largely escapes IGFBP regulation, IGF-1 LR3 is widely used as a cell-culture supplement and as a tool to study IGF-1 receptor signalling separately from binding-protein effects.
In dexamethasone-treated rats, LR3 IGF-1 was roughly 2.5 times more potent than native IGF-1 despite binding the IGF-1 receptor less strongly, an advantage the authors linked to its weak binding to IGF-binding proteins (Tomas et al., Biochemical Journal, 1992).
The roles of IGF-binding proteins, and why escaping them changes IGF-1 activity, are reviewed in Mohan and Baylink, Journal of Endocrinology, 2002. This literature is cited for scientific context only.
IGF-1 LR3 has an arginine at position 3 and a 13-amino-acid N-terminal extension. These changes sharply reduce binding to IGF-binding proteins, so more of the peptide stays available to the IGF-1 receptor.
IGF-1 LR3 is available as a 1mg lyophilized powder vial, shipped from Canada.
Store unopened vials in a cool, dry place away from direct light, with refrigeration recommended for long-term storage. After reconstitution, keep the vial refrigerated at 2–8°C.
Published literature is summarised for scientific context only. It is not a claim about this product, and this product is not for human or veterinary use.
Store unopened vials in a cool, dry environment away from direct light. For long-term storage, refrigeration is recommended. After reconstitution, keep refrigerated at 2–8°C and protect from direct light.
Not for human consumption. This product is sold exclusively as a research compound for in vitro and laboratory use by qualified researchers. It is not a drug, supplement, or cosmetic, is not intended for human or veterinary use, and is not intended to diagnose, treat, cure, or prevent any disease. No dosing, administration, or therapeutic claims are made or implied.
Published literature referenced on this page is provided for scientific context only and does not constitute a claim about this product or evidence of safety or efficacy in any organism.
By purchasing this product, you confirm that it will be used for legitimate research purposes in accordance with applicable laws and regulations.
