Introduction
Periostin, a 90 kDa disulfide-linked protein composed of 811 amino acids, was initially identified as an osteoblast-specific factor. This protein acts as a cell adhesion molecule for preosteoblasts and is believed to play a role in osteoblast recruitment, attachment, and spreading. Studies have shown that transforming growth factor beta-1 (TGFbeta1) and bone morphogenetic protein (BMP-2) significantly increase periostin expression. Structurally, OSF-2 comprises a typical signal sequence, a cysteine-rich domain, a fourfold repeated domain, and a C-terminal domain. Notably, the fourfold repeated domain of OSF-2 shares homology with the insect protein fasciclin. Periostin mRNA is expressed in the developing heart of mouse embryos and fetuses, specifically localizing to the endocardial cushions responsible for dividing the primitive heart tube into a four-chambered heart.
Description
OSF2 His-Tagged Fusion Protein Human, a 75 kDa protein, is produced in E. coli. It consists of 648 amino acid residues of human OSF-2 along with 23 additional amino acid residues, including a HisTag and an Xa-cleavage site.
Physical Appearance
White lyophilized powder, filtered for purity.
Formulation
The product is filtered through a 0.4 µm filter and lyophilized from a 0.5 mg/ml solution in 0.05M Acetate buffer with a pH of 4.
Solubility
To create a working stock solution of around 0.5 mg/ml, add 0.1M Acetate buffer (pH 4) to the lyophilized pellet and allow it to dissolve completely. For higher pH values, dilute the solution extensively with the appropriate buffer to a concentration of 10 µg/ml. This antigen's solubility is limited at higher concentrations. Note: This product is not sterile. Before using it in cell culture, filter it through a sterile filter.
Stability
Store the lyophilized protein at -20°C. After reconstitution, aliquot the product to prevent repeated freezing and thawing. Reconstituted protein remains stable at 4°C for a limited period; no changes are observed after two weeks at this temperature.
Purity
SDS-PAGE analysis indicates a purity greater than 90%.
Synonyms
OSF-2, Periostin, Osteoblast Specific Factor 2, PN OSF-2, PDLPOSTN, POSTN, MGC119510, MGC119511, PN, RP11-412K4.1.
Amino Acid Sequence
MGHHHHHHHH HHSSGHIEGR HMRNNHYDKI LAHSRIRGRD QGPNVCALQQ ILGTKKKYFS TCKNWYKKSI CGQKTTVLYE CCPGYMRMEG MKGCPAVLPI DHVYGTLGIV GATTTQRYSD ASKLREEIEG KGSFTYFAPS NEAWDNLDSD IRRGLESNVN VELLNALHSH MINKRMLTKD LKNGMIIPSM YNNLGLFINH YPNGVVTVNC ARIIHGNQIA TNGVVHVIDR VLTQIGTSIQ DFIEAEDDLS SFRAAAITSD ILEALGRDGH FTLFAPTNEA FEKLPRGVLE RFMGDKVASEALMKYHILNT LQCSESIMGG AVFETLEGNT IEIGCDGDSI TVNGIKMVNK KDIVTNNGVI HLIDQVLIPD SAKQVIELAG KQQTTFTDLV AQLGLASALR PDGEYTLLAP VNNAFSDDTL SMVQRLLKLI LQNHILKVKV GLNELYNGQI LETIGGKQLR VFVYRTAVCI ENSCMEKGSK QGRNGAIHIF REIIKPAEKS LHEKLKQDKR FSTFLSLLEA ADLKELLTQP GDWTLFVPTN DAFKGMTSEE KEILIRDKNA LQNIILYHLT PGVFIGKGFE PGVTNILKTT QGSKIFLKEV NDTLLVNELK SKESDIMTTN GVIHVVDKLL YPADTPVGND QLLEILNKLI KYIQIKFVRG STFKEIPVTV Y.
