RBP4 Human, His
Description
Functional Roles in Physiology
RBP4 serves as the exclusive transporter of retinol (vitamin A alcohol) in circulation. Key mechanisms include:
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Retinol Homeostasis: Maintains systemic retinol levels by shuttling hepatic stores to peripheral tissues (e.g., retina, adipose) .
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Thermogenesis Regulation: Overexpression in brown adipose tissue enhances energy expenditure and lipolysis in murine models .
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Insulin Signaling Modulation: Binds STRA6 receptors to activate JAK2/STAT5 pathways, suppressing insulin sensitivity in adipocytes .
Research Applications
RBP4 Human, His is utilized in diverse experimental contexts:
Metabolic Disease Studies
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Obesity/Diabetes: Elevated serum RBP4 correlates with insulin resistance. Genomic studies link RBP4 haplotypes to fasting insulin levels and type 2 diabetes risk (OR 1.37, 95% CI 1.05–1.79) .
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Cardiovascular Risk: Full-length RBP4 predicts coronary heart disease (CHD) risk in women within 8 years (OR 3.56, 95% CI 1.21–10.51) but not beyond 16 years .
Limitations and Controversies
Product Specs
Product Science Overview
Retinol Binding Protein-4 (RBP4) is a member of the lipocalin family and plays a crucial role in the transport of retinol (vitamin A alcohol) in the blood. This protein is essential for delivering retinol from liver stores to peripheral tissues, ensuring proper vitamin A distribution throughout the body .
RBP4 is a small protein with a molecular mass of approximately 21 kDa. The human recombinant version of RBP4, tagged with a His (histidine) tag, is produced using recombinant DNA technology. This His tag facilitates the purification of the protein through affinity chromatography, making it easier to isolate and study .
In the bloodstream, RBP4 forms a complex with retinol and interacts with another protein called transthyretin. This interaction prevents the loss of the RBP4-retinol complex through kidney filtration, ensuring that retinol is efficiently delivered to target tissues .
The recombinant human RBP4 with a His tag is typically produced in E. coli or human embryonic kidney (HEK293) cells. The His tag, usually consisting of six histidine residues, is added to the N- or C-terminus of the protein. This tag allows for easy purification using immobilized metal ion affinity chromatography (IMAC), which exploits the affinity of histidine residues for metal ions like nickel or cobalt .
