This Human FSTL1 overexpression lysate was created in HEK293 Cells and intented for use as a Western blot (WB) positive control. Purification of FSTL1 protein (Cat: 10924-H08H) from the overexpression lysate was verified.
A DNA sequence encoding the human FSTL1 (NP_009016.1) precursor (Met 1-Ile 308) with a carboxy-terminal polyhistidine tag was expressed.
The secreted recombinant human FSTL1 consists of 299 amino acids with the predicted molecular mass of 34.2 kDa. As a result of glycosylation, rhFSTL1 migrates as an approximately 47 kDa band in SDS-PAGE under reducing conditions.
Cell lysate was prepared by homogenization of the over-expressed cells in ice-cold modified RIPA Lysis Buffer with cocktail of protease inhibitors (Sigma). Cell debris was removed by centrifugation. Protein concentration was determined by Bradford assay (Bio-Rad protein assay, Microplate Standard assay). The cell lysate was boiled for 5 min in 1 x SDS loading buffer (50 mM Tris-HCl pH 6.8, 12.5% glycerol, 1% sodium dodecylsulfate, 0.01% bromophenol blue) containing 5% b-mercaptoethanol, and lyophilized.
Modified RIPA Lysis Buffer: 50 mM Tris-HCl pH 7.4, 150 mM NaCl, 1mM EDTA, 1% Triton X-100, 0.1% SDS, 1% Sodium deoxycholate, 1mM PMSF.
1. Centrifuge the tube for a few seconds and ensure the pellet at the bottom of the tube.
2. Re-dissolve the pellet using 200μL pure water and boil for 2-5 min.
1 X Sample Buffer (1 X modified RIPA buffer+1 X SDS loading buffer).
Stability & Storage
Store at 4℃ for up to twelve months from date of receipt. After re-dissolution, aliquot and store at -80℃ for up to twelve months. Avoid repeated freeze-thaw cycles.
Western Blot (WB)
Optimal dilutions/concentrations should be determined by the end user.
Human FRP Overexpression Lysate;Human FSL1 Overexpression Lysate;Human MIR198 Overexpression Lysate
Follistatin-related protein 1 (FSTL1) is an extracellular glycoprotein whose functional significance in physiological and pathological processes is incompletely understood. Recently, we have shown that FSTL1 acts as a muscle-derived secreted factor that is up-regulated by Akt activation and ischemic stress and that FSTL1 exerts favorable actions on the heart and vasculature. Here, we sought to identify the receptor that mediates the cellular actions of FSTL1. It contains an FS module, a follistatin-like sequence containing 10 conserved cysteine residues. FSTL1 is thought to be an autoantigen associated with rheumatoid arthritis. DIP2A functions as a novel receptor that mediates the cardiovascular protective effects of FSTL1. Experiment results have provided in vivo and in vitro evidence to demonstrate that Fstl1 modulates lung development and alveolar maturation, in part, through BMP4 signaling.
Rosenberg MI, et al. (2006) MyoD inhibits Fstl1 and Utrn expression by inducing transcription of miR-206. J Cell Biol. 175(1): 77-85.Ouchi N, et al. (2010) DIP2A functions as a FSTL1 receptor. J Biol Chem. 285(10): 7127-34.Geng Y, et al. (2011) Follistatin-like 1 (Fstl1) is a bone morphogenetic protein (BMP) 4 signaling antagonist in controlling mouse lung development. Proc Natl Acad Sci U S A. 108(17): 7058-63.