Growth and differentiation factor Associated Serum Protein (GASP) 1 and 2 are proteins known to be involved in the control of myostatin activity at least in vitro. Most deuterostome GASPs share a modular organization including WAP. follistatin/kazal. IGc2. https://www.soiebiologique.com/quick-sale-Axol-Friends-Mel-Axol-the-Axolotl-Black-Purple-special-save/