|Vector Type||Mammalian Expression Vector|
|Expression Method||Constiutive, Stable / Transient|
|Selection In Mammalian Cells||Hygromycin|
FLAG-tag, or FLAG octapeptide, is a polypeptide protein tag that can be added to a protein using recombinant DNA technology. It can be used for affinity chromatography, then used to separate recombinant, overexpressed protein from wild-type protein expressed by the host organism. It can also be used in the isolation of protein complexes with multiple subunits.
A FLAG-tag can be used in many different assays that require recognition by an antibody. If there is no antibody against the studied protein, adding a FLAG-tag to this protein allows one to follow the protein with an antibody against the FLAG sequence. Examples are cellular localization studies by immunofluorescence or detection by SDS PAGE protein electrophoresis.
The peptide sequence of the FLAG-tag from the N-terminus to the C-terminus is: DYKDDDDK (1012 Da). It can be used in conjunction with other affinity tags, for example a polyhistidine tag (His-tag), HA-tag or myc-tag. It can be fused to the C-terminus or the N-terminus of a protein. Some commercially available antibodies (e.g., M1/4E11) recognize the epitope only when it is present at the N-terminus. However, other available antibodies (e.g., M2) are position-insensitive.
Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that degrade components of the extracellular matrix (ECM) and play essential roles in various physiological and pathological processes such as morphogenesis, differentiation, angiogenesis, tissue remodeling, and tumor invasion. MMPs are synthesized as pro-enzymes and converted to active form by extracellular proteinases. MMP7, also referred to as matrilysin, is the smallest member of the MMP family and differs from other MMP members in that it lacks the C-terminal hemopexin-like domain. MMP7 is produced primarily by mucosal epithelia, and is capable of degrading various ECM proteins including proteoglycans, fibronectin, elastin and casein. This enzyme serves essential functions in both innate defense and wound healing, and appears to be one of the most important MMPs in human colon cancers. It has been reported that MMP7 contributes to tumor malignancy probably by cleaving cell surface proteins such as Fas ligand, degradation of IgG or inducing E-cadherin-mediated cell aggregation. In addition, matrilysin is also identified as a mediator of pulmonary fibrosis and a potential therapeutic target.