Looking for high-purity Follistatin for laboratory research? PX1 Research supplies USA-manufactured Follistatin with verified batch-to-batch consistency, lot-specific HPLC and mass spectrometry reports, and stringent endotoxin testing for rigorous preclinical assays.
Looking for high-purity Follistatin for laboratory research? PX1 Research supplies USA-manufactured Follistatin with verified batch-to-batch consistency, lot-specific HPLC and mass spectrometry reports, and stringent endotoxin testing for rigorous preclinical assays.
Follistatin (FS) is an autocrine single-chain glycoprotein expressed across diverse tissue types, primarily recognized in molecular biology for its potent binding affinity to members of the Transforming Growth Factor-Beta (TGF-β) superfamily. Discovered initially as an inhibitor of follicle-stimulating hormone (FSH) secretion from the anterior pituitary gland, subsequent in vitro assays revealed its pivotal role as a high-affinity antagonist to activin A and myostatin (Growth Differentiation Factor 8, or GDF-8). By sequestering these signaling ligands before they can engage cellular receptor complexes, Follistatin regulates downstream intracellular SMAD transcription pathways.
In modern cell biology and animal models, researchers utilize recombinant Follistatin to explore regulatory mechanisms governing skeletal muscle hypertrophy, muscular dystrophy models, tissue fibrosis, and metabolic homeostasis. As demand for high-integrity reagents grows, locating a reliable supplier offering verified follistatin sale inventory backed by comprehensive analytical data is essential for reproducible empirical outcomes. Laboratories require compounds manufactured under strict quality standards to ensure that non-specific cellular responses or endotoxin contamination do not compromise experimental data.
The primary sequence of human Follistatin encodes a precursor protein that undergoes post-translational processing and differential splicing to yield distinct biological isoforms. The most extensively researched variants in recombinant expression systems include Follistatin-288 (FS-288), Follistatin-315 (FS-315), and Follistatin-344 (FS-344). Each isoform features a specific structural domain organization comprising an N-terminal domain followed by three conserved Follistatin domains (FS1, FS2, and FS3), which contain cysteine-rich residues critical for disulfide bond formation and high-affinity ligand binding.
FS-288 is a truncated C-terminal variant exhibiting high affinity for cell-surface heparin sulfate proteoglycans, anchoring it tightly to local tissue matrices. Conversely, FS-315 represents the full-length circulating isoform, possessing a C-terminal extension that masks the heparin-binding sequence, allowing it to remain systemic until enzymatic cleavage occurs. FS-344 serves as the primary precursor transcript in recombinant expression cassettes. Understanding these structural variations is vital for investigators selecting reagents across all peptides for specific tissue-targeted or systemic preclinical research designs.
The primary biochemical mechanism of Follistatin centers on its ability to form irreversible, non-covalent stoichiometric complexes with TGF-β superfamily ligands. Preclinical literature indicates that one Follistatin dimer encapsulates activin A or myostatin, blocking the ligand's interaction with Type II activin receptors (ActRIIA and ActRIIB). By preventing ligand-receptor engagement, Follistatin inhibits the phosphorylation of receptor-regulated SMAD proteins (specifically SMAD2 and SMAD3), effectively silencing downstream gene transcription associated with muscle catabolism and extracellular matrix deposition.
In vitro binding kinetics demonstrate that Follistatin exhibits picomolar affinity ($K_d \approx 50-100\text{ pM}$) for activin A and low nanomolar affinity for GDF-8. This potent neutralizing capacity makes Follistatin a valuable molecular tool for dissecting signaling cross-talk between the ActRIIB pathway and anabolic cascades like Akt/mTOR. Investigators evaluating myostatin inhibition models routinely utilize purified Follistatin to establish baseline suppression metrics in skeletal muscle cell cultures and transgenic rodent strains.
Animal studies investigating Follistatin administration have demonstrated significant increases in skeletal muscle mass alongside marked reductions in fibrotic tissue markers. Transgenic murine models overexpressing Follistatin display a pronounced double-muscling phenotype without the visceral organ hypertrophy observed in alternative growth-factor manipulations. These preclinical findings suggest that localized inhibition of GDF-8 and activin A facilitates satellite cell activation, accelerates myoblast fusion, and enhances myofibrillar protein synthesis.
Beyond skeletal muscle, preclinical research has highlighted Follistatin's role in attenuating organ fibrosis. In rodent models of hepatic and renal impairment, Follistatin administration suppressed activin-mediated fibrogenesis by dampening alpha-smooth muscle actin ($\alpha$-SMA) expression and collagen deposition. Consequently, laboratories purchasing compounds from a certified follistatin sale rely on absolute sequence identity and high biological activity to evaluate these multi-organ therapeutic targets.
To properly contextualize Follistatin within muscle biology research, investigators often compare its affinity profile and downstream effects against other agents operating within the ActRIIB and regenerative pathways. The table and comparative analysis below illustrate key differences among common laboratory compounds:
While Follistatin functions as a direct ligand trap for both activin A and myostatin, synthetic decoy receptors such as Ace-031 bind a broader array of TGF-β ligands, including BMP-9 and BMP-10. Conversely, tissue-regenerative peptides like BPC-157 work through distinct angiogenic and growth factor upregulation pathways rather than direct SMAD signaling blockade. Selecting the appropriate compound depends entirely on whether the assay design targets isolated ligand neutralization or broader matrix repair signaling.
When procurement officers and principal investigators search for a verified follistatin sale, analytical rigor must take precedence over cost. Recombinant proteins produced in bacterial or mammalian expression vectors are susceptible to misfolding, aggregation, and residual host-cell impurities if purification protocols are suboptimal. A reliable vendor must provide comprehensive documentation detailing post-purification processing, lyophilization parameters, and purity benchmarks.
At PX1 Research, every production lot undergoes rigorous analytical testing in ISO 17025 accredited facilities. Investigators should mandate that any research peptide vendor supply a lot-specific Certificate of Analysis (COA) containing Reverse-Phase High-Performance Liquid Chromatography (RP-HPLC) chromatograms and Electrospray Ionization Mass Spectrometry (ESI-MS) spectra to confirm both chemical purity and correct molecular mass prior to assay integration.
High-performance liquid chromatography is the gold standard for quantifying sequence purity and detecting degradation products or truncated peptide fragments. PX1 Research guarantees that all Follistatin lots demonstrate $\ge 98\%$ main-peak purity via analytical RP-HPLC. Complementing HPLC, ESI-MS verifies that the experimental mass matches the theoretical molecular weight of the target sequence, ensuring no unexpected amino acid substitutions or improper disulfide linkage patterns exist.
Equally critical for biological assays is stringent endotoxin screening. Endotoxins (lipopolysaccharides derived from Gram-negative bacterial cell walls) can trigger non-specific inflammatory signaling in cell culture and animal models, confounding experimental data. PX1 Research utilizes Chromogenic Recombinant Factor C or Limulus Amebocyte Lysate (LAL) testing to confirm endotoxin levels remain below $< 0.01\text{ EU/mg}$, providing pristine reagents suitable for sensitive in vitro research.
Maintaining the structural integrity of recombinant Follistatin requires precise laboratory handling protocols. Lyophilized Follistatin should be stored at $-20^\circ\text{C}$ to $-80^\circ\text{C}$ upon receipt. Prior to opening the vial, allow the container to equilibrate to room temperature to prevent atmospheric moisture condensation on the lyophilized cake.
Reconstitution should be performed using sterile, bacteriostatic or sterile deionized water, depending on downstream assay requirements. For long-term stock solution stability, reconstituted protein should be diluted into a buffer containing a carrier protein (such as $0.1\%$ Bovine Serum Albumin) to prevent non-specific adsorption to plastic microcentrifuge tubes. Avoid repeated freeze-thaw cycles by aliquoting the stock solution into single-use experimental volumes, storing them at $-80^\circ\text{C}$.
PX1 Research is committed to advancing scientific discovery by providing researchers across academic, institutional, and biotechnology sectors with unmatched chemical quality. All compounds offered through our follistatin sale catalog are manufactured in state-of-the-art, GMP-compliant facilities within the United States, eliminating the supply chain uncertainty and quality variability associated with unverified overseas sourcing.
We support research teams with flexible procurement options, offering single-vial orders for exploratory studies alongside specialized wholesale lab accounts for high-throughput screening initiatives. With dedicated fulfillment operations based out of California and Arizona, PX1 Research provides same-day shipping on orders placed Monday through Friday before 3:00 PM EST, ensuring your laboratory maintains seamless operational continuity.
What is the primary application of Follistatin in laboratory research?
Follistatin is supplied exclusively as a research compound for in vitro assays and animal models studying TGF-beta signaling, myostatin inhibition, satellite cell differentiation, and tissue fibrosis. It is not for human or veterinary use.
How does PX1 Research verify the purity of its Follistatin?
Every lot of Follistatin undergoes rigorous testing in an ISO 17025 accredited laboratory using Reverse-Phase High-Performance Liquid Chromatography (RP-HPLC) for purity quantification and Electrospray Ionization Mass Spectrometry (ESI-MS) for molecular weight verification.
What endotoxin levels are acceptable for research-grade Follistatin?
PX1 Research mandates strict endotoxin thresholds, ensuring all Follistatin lots test at less than 0.01 EU/mg via LAL assays to prevent endotoxin-induced cellular toxicity or inflammatory artifacts during experiments.
What is the difference between Follistatin-288, Follistatin-315, and Follistatin-344?
FS-288 is a tissue-bound isoform with high heparin affinity; FS-315 is the major circulating isoform in vivo; FS-344 is the precursor transcript typically utilized in recombinant expression systems to yield functional biological variants.
How should lyophilized Follistatin be reconstituted for laboratory use?
Reconstitute the lyophilized powder using sterile reconstituted water or buffer solution. Gently swirl without vigorous vortexing to avoid protein denaturation, and dilute with a carrier protein (e.g., 0.1% BSA) if storing low-concentration aliquots.
What are the recommended storage conditions for Follistatin?
Lyophilized vials should be stored at -20°C to -80°C. Once reconstituted, stock solutions should be aliquoted to avoid repeated freeze-thaw cycles and kept at -80°C for extended stability.
Where is PX1 Research Follistatin manufactured and shipped from?
All PX1 Research compounds are manufactured in USA-based, GMP-compliant facilities. Orders are fulfilled directly from our logistics centers in California and Arizona with same-day shipping on business days.
Can lab accounts purchase Follistatin in bulk quantities?
Yes, PX1 Research offers tiered pricing and dedicated support for institutional accounts through our wholesale portal, accommodating bulk procurement needs for large-scale preclinical studies.
All products are sold strictly for laboratory and research use only. Not for human or veterinary use, diagnosis, treatment or consumption. Statements have not been evaluated by the FDA.