Fibrillin-1/Asprosin Protein, Human (HEK293, His)

Fibrillin-1 and Asprosin are two proteins generated from the same precursor protein, which is encoded by the Fibrillin 1 gene, through proteolytic cleavage. Fibrillin-1 protein, a member of the fibrillin family, is a crucial structural protein in the formation of microfibrils in the extracellular matrix, maintaining tissue homeostasis and cell adhesion, regulating the availability of growth factors, and inhibiting osteoclastogenesis. In contrast, Asprosin is a hormone primarily secreted by white adipose tissue and is involved in regulating glucose metabolism within the body. Fibrillin-1/Asprosin protein, Human (HEK293, His) is a recombinant protein expressed in HEK293 cells with an N-terminal His tag, comprising a full length of 140 amino acids (S2732-H2871)^{[1][2][3][4][5][6][7][8][9][10][11]}.

Fibrillin-1 is a key structural protein in the formation of extracellular matrix microfibrils. It plays a critical role in maintaining the structural integrity and functional stability of connective tissues, not only providing physical support but also participating in the regulation of tissue homeostasis and bone metabolism through interactions with various growth factors, integrins, and heparin.
1. Physical Structural Support:
(1) In tissues such as the lung, blood vessels, and skin, Fibrillin-1 supports the formation of elastic fibers^[1].
(2) In tissues lacking elastin, such as the ciliary zonule, tendon, cornea, and glomerulus, Fibrillin-1 provides structural support^[1].
2. Homeostasis Regulation and Metabolic Control:
(1) Fibrillin-1 maintains tissue structural stability through specific interactions with growth factors (such as bone morphogenetic proteins (BMPs), growth and differentiation factors (GDFs), latent transforming growth factor beta-binding proteins (LTBPs)), cell surface integrins, and other extracellular matrix proteins and proteoglycan components^[1].
(2) Fibrillin-1 inhibits osteoclastogenesis by binding to the osteoclast differentiation factor TNFSF11 and suppressing the TNFSF11-mediated nuclear translocation and activation of the transcription factor NFATC1, thereby influencing bone metabolism^[2].
Fibrillin-1 mediates cell adhesion by binding to cell surface receptors integrins ITGAV and ITGA5^[3][4]. It can also bind heparin, ensuring the proper assembly of microfibrils^[5].
Asprosin is a hormone secreted by white adipose tissue that plays a crucial role in regulating energy balance in the body, particularly in maintaining blood glucose levels during fasting. Asprosin acts on the liver during fasting by binding to the olfactory receptor OR4M1 on hepatocytes, activating protein kinase A (PKA), and triggering the rapid release of glucose into the bloodstream. Asprosin also promotes rapid glucose release by activating the G protein-cAMP-PKA pathway^[6][7][8][9].

Fibrillin-1 protein (Human) (0-20 μg/mL, 48 h) promotes αvβ3 and α5β1 integrin-mediated adhesion of human umbilical vein endothelial cells in a dose-dependent manner and enhances their proliferation and migration at a dose of 1 μg/mL^[10].

Asprosin protein (human) (2 mg/kg, i.p., single dose, with blood samples collected 48 hours or 7 days after administration) has a cardioprotective effect in Isoprenaline hydrochloride (HY-B0468)-induced myocardial infarction rat models^[11].

1.Measured by its binding ability in a functional ELISA. Immobilized Human MFAP4 at 0.5 μg/mL (100 μL/well) can bind Biotinylated Human Fibrillin-1. The ED₅₀ for this effect is ≤0.8473 μg/mL, corresponding to a specific activity is ≥1.18×10³ Unit/mg.
2.Measured by its ability to induce TNF-ɑ secretion by macrophages produced by THP-1 cells treated with dihydroxyvitamin D3.

• 
  Measured by its binding ability in a functional ELISA. Immobilized Human MFAP4 at 0.5 μg/mL (100 μL/well) can bind Biotinylated Human Fibrillin-1. The ED₅₀ for this effect is 0.6163 μg/mL, corresponding to a specific activity is 1.62×10³ Unit/mg.

Human

HEK293

N-8*His

P35555 (S2732-H2871)

2200  [NCBI]

STNETDASNIEDQSETEANVSLASWDVEKTAIFAFNISHVSNKVRILELLPALTTLTNHNRYLIESGNEDGFFKINQKEGISYLHFTKKKPVAGTYSLQISSTPLYKKKELNQLEDKYDKDYLSGELGDNLKMKIQVLLH

Approximately 25-33 kDa due to the glycosylation.

• 
  Greater than 95% as determined by reducing SDS-PAGE.

Lyophilized powder

Lyophilized from a 0.2 μm filtered solution of PBS or 20 mM PB, 150 mM NaCl, pH 7.4 or PBS, pH 7.4, 8% trehalose.

<1 EU/μg, determined by LAL method.

It is not recommended to reconstitute to a concentration less than 100 μg/mL in ddH₂O. For long term storage it is recommended to add a carrier protein (0.1% BSA, 5% HSA, 10% FBS or 5% Trehalose).

Stored at -20°C for 2 years. After reconstitution, it is stable at 4°C for 1 week or -20°C for longer (with carrier protein). It is recommended to freeze aliquots at -20°C or -80°C for extended storage.

Room temperature in continental US; may vary elsewhere.

• [1]. Jensen SA, et al. New insights into the structure, assembly and biological roles of 10-12 nm connective tissue microfibrils from fibrillin-1 studies. Biochem J. 2016 Apr 1;473(7):827-38.  [Content Brief]

  [2]. Tiedemann K, et al. Fibrillin-1 directly regulates osteoclast formation and function by a dual mechanism. J Cell Sci. 2013 Sep 15;126(Pt 18):4187-94.  [Content Brief]

  [3]. Bax DV, et al. Cell adhesion to fibrillin-1 molecules and microfibrils is mediated by alpha 5 beta 1 and alpha v beta 3 integrins. J Biol Chem. 2003 Sep 5;278(36):34605-16.  [Content Brief]

  [4]. Jovanovic J, et al. alphaVbeta6 is a novel receptor for human fibrillin-1. Comparative studies of molecular determinants underlying integrin-rgd affinity and specificity. J Biol Chem. 2007 Mar 2;282(9):6743-51.  [Content Brief]

  [5]. Tiedemann K, et al. Interactions of fibrillin-1 with heparin/heparan sulfate, implications for microfibrillar assembly. J Biol Chem. 2001 Sep 21;276(38):36035-42.  [Content Brief]

  [6]. Romere C, et al. Asprosin, a Fasting-Induced Glucogenic Protein Hormone. Cell. 2016 Apr 21;165(3):566-79.  [Content Brief]

  [7]. Lee T, et al. Asprosin impairs insulin secretion in response to glucose and viability through TLR4/JNK-mediated inflammation. Mol Cell Endocrinol. 2019 Apr 15;486:96-104.  [Content Brief]

  [8]. Li E, et al. OLFR734 Mediates Glucose Metabolism as a Receptor of Asprosin. Cell Metab. 2019 Aug 6;30(2):319-328.e8.  [Content Brief]

  [9]. Li E, et al. OLFR734 Mediates Glucose Metabolism as a Receptor of Asprosin. Cell Metab. 2019 Aug 6;30(2):319-328.e8.  [Content Brief]

  [10]. Mariko B, et al. Microfibrils and fibrillin-1 induce integrin-mediated signaling, proliferation and migration in human endothelial cells. Am J Physiol Cell Physiol. 2010 Nov;299(5):C977-87.  [Content Brief]

  [11]. Onat E, et al. The protective effects of humanin in rats with experimental myocardial infarction: The role of asprosin and spexin. Heliyon. 2023 Jul 26;9(8):e18739.  [Content Brief]