Clusterin Rat

Clusterin, also known as Apolipoprotein J (APO-J), is a protein with a molecular weight of 75-80 kDa. It exists as a heterodimer linked by disulfide bonds and is heavily glycosylated with sialic acid. However, truncated forms targeted to the nucleus have also been observed. The precursor polypeptide undergoes proteolytic cleavage to remove a 22-amino acid signal peptide and further cleavage between residues 227 and 228, resulting in the formation of 'a' and 'b' chains. These chains assemble in an anti-parallel orientation, forming a heterodimer. The cysteine-rich regions within the chains are connected by five disulfide bridges and are flanked by two coiled-coil alpha-helices and three amphipathic alpha-helices. Clusterin exhibits a high degree of sequence conservation across various species, with 70% to 80% homology. It is ubiquitously expressed in most mammalian tissues and is found in various bodily fluids like plasma, milk, urine, cerebrospinal fluid, and semen. Clusterin interacts with a wide range of molecules, including immunoglobulins, lipids, heparin, bacteria, complement proteins, paraoxonase, beta-amyloid, leptin, and others. It has been implicated in numerous biological processes, including phagocyte recruitment, aggregation induction, complement regulation, apoptosis inhibition, membrane remodeling, lipid transport, hormone transport, and scavenging, as well as matrix metalloproteinase inhibition. Although the precise function of clusterin remains elusive, one prominent hypothesis suggests its role as an extracellular chaperone, safeguarding cells from stress-induced damage caused by aggregated and misfolded protein precipitates. Clusterin expression levels, both at the mRNA and protein level, are altered in various pathological conditions and clinically relevant situations, including cancer, organ regeneration, infection, Alzheimer's disease, retinitis pigmentosa, myocardial infarction, renal tubular damage, autoimmunity, and others.

The Clusterin Rat His-Tagged Fusion Protein, expressed in E. coli, is a 26.5 kDa protein. It comprises 215 amino acids of Rat APO-J and an additional 25 amino acids from tags: a T7-Tag (16 amino acids) at the N-terminus and a His-Tag (9 amino acids) at the C-terminus. (Underlined for emphasis).

White powder, freeze-dried.

The protein solution, at a concentration of 0.5 mg/ml in 0.02 M Tris buffer with 0.05 M NaCl (pH 7.5), was filtered through a 0.4 micrometer filter and then lyophilized.

To prepare a working solution, it is recommended to reconstitute the lyophilized powder in deionized water to a concentration of 0.5 mg/ml. Allow the powder to dissolve completely. This product is not sterile. Prior to use in cell culture, filter the solution using an appropriate sterile filter.

The lyophilized protein should be stored at -20°C. After reconstitution, aliquot the protein solution to minimize freeze-thaw cycles. The reconstituted protein can be stored at 4°C for a limited period; no significant changes were observed after two weeks of storage at 4°C.

Purity of the protein is greater than 90%, as determined by SDS-PAGE analysis.

CLI, AAG4, KUB1, SGP2, SGP-2, SP-40, TRPM2, MGC24903, Complement-associated protein SP-40,40, Complement cytolysis inhibitor, NA1/NA2, Apolipoprotein J, Apo-J, Testosterone-repressed prostate message 2, TRPM-2.

Escherichia Coli.

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