Recombinant Human Klotho His-tag Protein, CF

Recombinant Human Klotho His-tag Protein, CF Summary

Product Specifications

Product Datasheets

Carrier Free

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

Background: Klotho

Klotho, also called alpha-Klotho ( alpha -Klotho), is the founding member that along with beta -Klotho and gamma -Klotho, form the Klotho family within the glycosidase-1 superfamily (1, 2). alpha -Klotho is a type I transmembrane protein consisting of a large extracellular domain (ECD) containing glycosidase-like domains (KL1 and KL2), a single transmembrane domain and a short intracellular domain. Alternative mRNA splicing of the ECD of alpha -Klotho results in a circulating protein known as soluble alpha -Klotho (s‑Klotho), which has been detected in both humans and mice (3, 4). In addition to the s-Klotho form, a 130 kDa form found in plasma and cerebrospinal fluid and a prominent intracellular 120 kDa form of alpha -Klotho have also been identified (3, 4). The mature ECD of full length human alpha -Klotho shares 87% and 90% identity with mouse and rat alpha -Klotho, respectively. Due to highly conserved sequences between alpha -Klotho forms, it is difficult to differentiate s-klotho from the other short forms in vivo (5). Although alpha -Klotho was identified ~20 years ago, its function remains incompletely understood. alpha -Klotho shows weak glucuronidase activity which activates the renal ion channel TRPV5 to reabsorb urinary calcium (10). alpha -Klotho acts as a cofactor for interaction of FGF-23 with FGF R1 (6). This interaction negatively regulates 1 alpha -hydroxylase, the rate-limiting enzyme in the synthesis of 1,25(OH)2D3 (vitamin D) (7). s-Klotho functions as a hormonal factor and is involved in anti-aging, anti-oxidation, modulation of ion-transport, and Wnt signaling (8). Both alpha -Klotho and beta -Klotho are cofactors for FGF19 binding (9). The phenotype of alpha ‑Klotho-deficient mice resembles premature aging, including arteriosclerosis, osteoporosis, skin atrophy, infertility, emphysema and premature death (2). alpha -Klotho deficient mice show severe hyperphosphatemia and ectopic calcification of soft tissues due to excess vitamin D (2-7). Conversely, excess alpha -Klotho extends lifespan (6).

Related Research Areas

• FGF Family
• Glycobiology-related Enzymes
• Lipid/Cholesterol Metabolism
• Lysosomal Enzymes
• Renal Markers
• Search Bioprocessing Enzymes
• Search Glycobiology-related Enzymes