Background
Klotho is a glycosylated protein that plays an important role in the regulation of phosphate and calcium homeostasis. The full length transmembrane form has a large extracellular domain composed of two homologous subunits termed KL1 and KL2, which contain 516 and 439 amino acid residues, respectively, The predominant circulating form, which is derived from alternative RNA splicing, contains the KL1 subunit and constitutes the N-terminal sequence of transmembrane Klotho. A third Klotho protein of about 128 kDa has been identified in the blood and cerebrospinal fluid. This circulating protein arises from the action of an as yet unidentified protease which cleaves transmembrane Klotho just above and/or within the plasma membrane. Klotho has been shown to play a key role in the signaling cascade of fibroblast growth factor-23 (FGF-23), a bone derived hormone that acts in the kidney to inhibit phosphate reabsorption and vitamin D biosynthesis. Klotho promotes FGF-23 signaling through binding to FGFRI (IIIc) which converts this canonical FGF receptor into a specific receptor for FGF-23. In the absence of Klotho the function of FGF-23 is literally abolished. Recombinant human Klotho is a 65-70 kDa glycoprotein containing 516 amino acid residues.
Specifications
Additional Names
?Klotho, KLAPreparation
Biological activity was determined by the dose - dependent stimulation of the proliferation of murine NIH - 3T3 cells. Recombinant human Klotho is effective in a concentration range of 0.5 - 2.0 μg/ml.Location
EPGDGAQTWA RFSRPPAPEA AGLFQGTFPD GFLWAVGSAA YQTEGGWQQH GKGASIWDTF THHPLAPPGD SRNASLPLGA PSPLQPATGD VASDSYNNVF RDTEALRELG VTHYRFSISW ARVLPNGSAG VPNREGLRYY RRLLERLREL GVQPVVTLYH WDLPQRLQDA YGGWANRALA DHFRDYAELC FRHFGGQVKY WITIDNPYVV AWHGYATGRL APGIRGSPRL GYLVAHNLLL AHAKVWHLYN TSFRPTQGGQ VSIALSSHWI NPRRMTDHSI KECQKSLDFV LGWFAKPVFI DGDYPESMKN NLSSILPDFT ESEKKFIKGT ADFFALCFGP TLSFQLLDPH MKFRQLESPN LRQLLSWIDL EFNHPQIFIV ENGWFVSGTT KRDDAKYMYY LKKFIMETLK AIKLDGVDVI GYTAWSLMDG FEWHRGYSIR RGLFYVDFLS QDKMLLPKSS ALFYQKLIEK NGFPPLPENQ PLEGTFPCDF AWGVVDNYIQ VSQLTKPISS LTKPYHSource
CHO cells (Chinese Hamster Ovarian cells)Reactivity
n/aTested Application
n/aStorage
The lyophilized Klotho recombinant protein is stable for at least 2 years from date of receipt at -20ËšC. Reconstituted Klotho is stable for at least 3 months when stored in working aliquots with a carrier protein at -20ËšC. As with any protein, exposing Klotho recombinant protein to repeated freeze / thaw cycles is not recommended. When working with proteins care should be taken to keep recombinant protein at a cool and stable temperature.Species Reactivity
n/aPurity
Greater than 98% by SDS-PAGE gel and HPLC analyses.Endotoxin level is less than 0.1 ng per μg (1EU/μg).
