# ACE-031

> Soluble ActRIIB-Fc fusion used in research as a myostatin-capturing decoy

All products are sold strictly for laboratory research use only. Not for human or veterinary use.

- Web page: https://peptidemedixeu.com/en/products/ace-031/
- Brand: Peptide Medix EU
- Category: [IGF & Muscle Peptides](https://peptidemedixeu.com/en/collections/igf-peptides/)
- Purity: ≥95% by SDS-PAGE and HPLC; lot-matched COA available
- from €191 (EUR)

## Sizes and prices (EUR)

| Size | Price | SKU |
| --- | --- | --- |
| 1 mg | €191 | ACE-031-1-MG |

_Catalog prices at build time; the web page and checkout are authoritative._

## Specifications

- **Form:** Lyophilized recombinant protein, sealed glass vial
- **Purity:** ≥95% by SDS-PAGE and HPLC; lot-matched COA available
- **Available sizes:** 1 mg
- **Solubility:** Sterile or bacteriostatic water; carrier protein often added for dilute stocks
- **Storage (lyophilized):** −20 °C, protected from light and moisture
- **Storage (reconstituted):** 2–8 °C for immediate work; aliquot and freeze for longer studies
- **Protein class:** Fc-fusion protein; soluble activin receptor type IIB decoy
- **Construct:** Extracellular domain of human ActRIIB fused to human IgG1 Fc
- **Quaternary structure:** Disulfide-linked homodimer, as with other IgG1 Fc fusions
- **Principal binding partners:** Myostatin (GDF-8), activin A, GDF-11 and selected BMPs
- **Also known as:** ActRIIB-Fc, soluble activin receptor type IIB fusion protein, ramatercept
- **Research areas:** Myostatin-pathway inhibition, muscle-mass regulation, muscular dystrophy models, bone density models

## Description

ACE-031 is a recombinant fusion protein: the extracellular, ligand-binding part of human activin receptor type IIB (ActRIIB) fused to the Fc region of human IgG1. Instead of occupying a receptor on the cell membrane, it acts as a decoy in solution — myostatin, activin A and other TGF-β superfamily ligands attach to the soluble receptor domain and are thereby withdrawn from the pool that could signal via membrane ActRIIB. The Fc segment makes the molecule a dimer and gives it a far longer circulating half-life than the bare receptor fragment.

How broadly it captures ligands is what defines its experimental value. Besides myostatin, the soluble ActRIIB domain binds activin A, GDF-11 and a number of bone morphogenetic proteins, so a phenotype cannot be credited to myostatin blockade unless more selective reagents are run in parallel — the reason we stock the myostatin propeptide and follistatin-344 alongside it. Being a recombinant protein rather than a synthetic peptide, it is released against a 95% SDS-PAGE and HPLC specification instead of the 99% HPLC limit used for short sequences, and it needs protein-style handling: the disulfide-bonded Fc homodimer aggregates if shaken hard or frozen and thawed repeatedly, so reconstitute gently, add carrier protein to dilute stocks and aliquot the single 1 mg vial before freezing.

## Frequently asked questions

### What is ACE-031, precisely?

A recombinant fusion of the ligand-binding extracellular domain of human activin receptor type IIB with the Fc portion of human IgG1. The receptor domain traps myostatin and related ligands, while the Fc part forms the dimer and prolongs the molecule's lifetime in circulation.

### How does it compare with Follistatin-344?

Both neutralise ligands of the same pathway, but by different routes. Follistatin is a native binding protein that envelops activin and myostatin, whereas ACE-031 is an engineered, soluble version of the receptor. Many study designs include both as side-by-side arms.

### Is ACE-031 tested by an independent lab?

Yes. An independent laboratory analyses every lot, measuring purity by SDS-PAGE and HPLC and confirming identity with suitable protein techniques. The certificate of analysis carries your vial's lot number and is available on request.

### What storage does ACE-031 need?

Store unopened lyophilised vials at −20 °C away from light and moisture. Once reconstituted, keep at 2–8 °C for work that follows immediately, or aliquot and freeze for longer projects. Fc-fusion proteins aggregate with repeated freeze–thaw and rough mixing, so avoid both.

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All products offered on this website are intended solely for in-vitro laboratory research and development by qualified professionals. They are not drugs, foods, cosmetics or dietary supplements, and are not intended to diagnose, treat, cure or prevent any disease. Products must not be introduced into humans or animals in any manner. By purchasing, you confirm that you are a qualified researcher and accept full responsibility for handling and storage in accordance with applicable laws.

Peptide Medix EU · https://peptidemedixeu.com/en/products/ace-031/