IGF-1 LR3 vs IGF-1 DES — Research Comparison

IGF-1 LR3 vs IGF-1 DES

IGF-1 LR3 and IGF-1 DES are distinct analogs of insulin-like growth factor-1. Both alter the N-terminal region, but they do so in opposite ways and support different controlled research questions.

Structural comparison

IGF-1 LR3 is an 83-amino-acid analog with a 13-amino-acid N-terminal extension and an arginine substitution at position 3. IGF-1 DES is a truncated 67-amino-acid variant lacking residues 1–3 of native IGF-1.

| Feature | IGF-1 LR3 | IGF-1 DES | |---|---|---| | Sequence length | 83 amino acids | 67 amino acids | | Defining change | N-terminal extension plus Arg3 substitution | Removal of N-terminal residues 1–3 | | Research profile | Extended signalling window | Short-window, localized signalling | | Shared receptor | IGF-1R | IGF-1R | | Primary distinction | Reduced IGFBP affinity with extended persistence | Reduced IGFBP interaction through truncation |

Signalling comparison

Both variants are studied through IGF-1R phosphorylation and downstream PI3K-AKT-mTOR and RAS-MAPK measurements. LR3-focused work emphasizes duration and sustained pathway observation. DES-focused work emphasizes localized or short-window responses. Results depend on the model, matrix, controls, and measurement interval.

Avoiding identity overlap

A study should record the complete compound name, sequence identity, batch identifier, and analytical method. A generic “IGF-1” label is insufficient because native IGF-1, LR3, and DES have different structures and experimental profiles.

Research scope

This comparison covers molecular identity, receptor interactions, and laboratory pathway endpoints only. Its scope is limited to molecular identity, receptor interaction, and laboratory pathway endpoints.

References

• Bryant KJ et al. Long R3 IGF-I mutein characterization. Growth Factors. 1996.
• Ballard FJ et al. DES(1-3)IGF-I structural review. International Journal of Biochemistry & Cell Biology. 1996.
• Mongongu C et al. High-resolution mass-spectrometry detection of IGF-I variants. Drug Testing and Analysis. 2021.

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