Retinol-binding protein 4 Antibodies

Retinol-binding protein 4 (RBP4)

Retinol-binding protein that mediates retinol transport in blood plasma (PubMed:5541771). Delivers retinol from the liver stores to the peripheral tissues (Probable).

Transfers the bound all-trans retinol into STRA6, that then facilitates retinol transport throughout the cell membrane (PubMed:22665496). .

Gene Information

Human
Gene Name:	RBP4
Uniprot:	P02753
Entrez:	5950

Family

Belongs to:
calycin superfamily

Alternative Names

interstitial; Plasma retinol-binding protein; RBP4; retinol binding protein 4, plasma; RetinolBinding Protein 4; retinol-binding protein 4, plasma

Molecular Weight

Mass (kDA):
23.01 kDA

Genomic Context

Human
Location:	10q23.33
Sequence:	10; NC_000010.11 (93591694..93601744, complement)

Tissue Specificity

Detected in blood plasma and in urine (at protein level).

Subcellular Localizations

Secreted.

Diseases

• Insulin Resistance
• Obesity
• Diabetes Mellitus
• Diabetes Mellitus, Non-insulin-dependent
• Insulin Sensitivity
• Inflammation
• Metabolic Syndrome X
• Impaired Glucose Tolerance
• Fatty Liver
• Cardiovascular Diseases
• Liver Diseases
• Hypertensive Disease

• Steatosis
• Dyslipidemias
• Kidney Diseases
• Steatohepatitis
• Polycystic Ovary Syndrome
• Atherosclerosis
• Nonalcoholic Fatty Liver Disease

Interacting Proteins

• TTR

Pathways

• Pathogenesis
• Secretion
• Transport
• Glomerular Filtration
• Insulin Secretion
• Glucose Homeostasis
• Excretion
• Immune Response
• Energy Homeostasis
• Aging
• Retinol Transport
• Glucose Transport
• Localization

• Fatty Acid Oxidation
• Cell Adhesion
• Cell Differentiation
• Parturition
• Ovulation
• Regulation Of Glucose Homeostasis
• Coagulation

PTMs

• Oxidation
• Phosphorylation
• Cleavage
• Methylation

• Demethylation
• Reduction
• Glycosylation
• Acylation

For details, visit:
bosterbio.com/bosterbio-gene-info-cards/RBP4

Best Uses Of The RBP4 Marker

An antibody called His-tag has been used to confirm the RBP4 marker. This antibody was developed specifically for this antigen. The RBP4 protein has moderate flexibility regions, and local hydrophilicity. This marker was also confirmed by the use of an anti His-tag antibody. Those findings support the idea that this protein antigen could be an excellent biomarker.

Local hydrogenphilicity of the RBP4 protein antigen was favorable

Recent research has proven that the Boster Bio RBP4 antigen peptide is associated with a favorable local hydrophilicity. This peptide can be used as a marker to diagnose HCC. To determine the presence of the antigen within liver tissue, the researchers utilized the RBP4 protein. The results were compared with the results of previous studies published. The authors conclude that RBP4 expression is a promising marker for HCC.

The expression levels of RBP4 were associated with the progression of HCC and the prognosis for the patient. The results from the TCGA and UALCAN databases also confirmed that low RBP4 expression levels were associated with poor prognosis. Incredibly, the high expression levels of RBP4 did not correlate with poor prognosis. The results of this study are favorable.

After constructing the plasmid that expresses the RBP4 gene fragment the recombinant bacterial culturing was verified by RT-PCR. The target sequence fragment was 600 bp in length. The PCR product was then transferred into cells that are DH5a-competent. The plasmid was then digested with Hind III and BamH I enzymes. After 4 hours the bacteria's pellet was broken.

The RBP4 protein that is closely linked to the liver, plays an essential function in the diagnosis and prognosis of tumors. Because it binds to the natural RBP4 protein, an anti-RBP4 antibody was chosen with high specificity. The mAb was able to examine HCC using immunohistochemistry and adjacent non-tumorous liver tissue.

The results revealed that Boster Bio RBP4 protein antigen was favorable in the local hydrophilic environment. Recombinant RBP4 can bind retinol. The retinol molecules are soluble within the aqueous milieu because of the b-barrel core of the protein. It then flows through the bloodstream.

RBP4's biological functions are apparent from molecular models. It may play a part in pathology and is associated with high serum levels. The gene that is corresponding to it, RBP4, is expressed in the cerebrospinal fluid and is likely secreted by the choroid cells of the plexus. The antigen is expressed in different tissues, including the liver, colon and pancreas.

The local hydrophilicity of RBP4 may also be related to its role in stimulating lipolysis. Hence, the antigen might be involved in the regulation of brown adipogenesis. It could be a transport protein or a binding protein for the fatty acid. More research is needed to determine the implication of RBP4 in these processes. As of now, there are only a few studies that have examined the role of RBP4 in the liver.

In addition to its function in adiponectin, RBP4 is expressed in various areas of the central nervous system including the retina. However, the role of RBP4 in the brain is not fully understood. RBP4-deficient mice exhibit decreased locomotor activity, anxiety, and less proliferating cells in the subventricular area. This change in vitamin A transport may be detrimental to neuronal functionand behavior, development, and other aspects.

Surface potential of the protein antigen RBP4 and flexibility regions were moderate

Boster Bio RBP4 antibody was selected based on its affinity for the antigen. The EC50 values of the anti-RBP4 antigen in different concentrations were 0.197 mg mL-1 to 0.166 ug mL-1 and 0.122 ug mg mL-1. The affinity constant was 3.98 x 108 L*mol-1 and determined using an ELISA plate containing RBP4His, SAA4-His, recombinant SHBG-His and NEK2-His proteins.

These findings were backed by studies on mice models and mutations in the human RBP4 proteins. The research was supported by the German Research Foundation, Austrian Science Fund and the Open Access Publication Fund. All authors have read and are able to approve the manuscript. Boster Bio RBP4 protein surface potential and flexibility areas were moderately supportive of the research. Researchers also noted that the Boster bio RBP4 protein antigen's surface possibility and flexibility regions were moderate.

The aim of this study was to isolate the Boster bio RBP4 antigen protein from the cell line carrying the Boster B7.8 phage gene. It was used as an RTPCR template. The results indicated that the RBP4 protein cloned binds specifically to the anti-His antibody. The RBP4 protein was then transferred to DH5a competent cells, and digested with BamH I and Hind III enzymes. The bacterial pellet was later broken by ultrasonic disruption.

The RBP4 antibody cloned from a human cell type and tissue sample is able to recognize retinol. The results suggest that the RBP4 protein-antigen has a physiological function for fatty acid transport and metabolism. It could play an important role in maintaining healthy weight and blood glucose levels. These results will require further study.

Using the TCGA database, the researchers found that the expression of RBP4 in HCC cells was consistent with results from The Cancer Genome Atlas (TCGA) database. They also discovered that lower RBP4 expression was associated to an eminent prognosis. A high level of RBP4 were associated with a greater risk of breast cancer in smokers as compared to those who did not smoke.

Additionally, an anti-RBP4 antibody mAb was produced as well. The mAb was derived from monoclonal hybridoma cells which secrete IgG subtype antibodies. Monoclonal monoclonal mAbs can attach to antigens effectively and are stable. This antibody has moderate affinity for RBP4 antigens. The mAb also has high specificity and fairly high affinity.

Although the RBP4 Truncated protein has a small amount of flexibility in its surface area it still has the ability to bind retinol. However, the physiological function of the truncated protein is unclear. A tiny amount of retinol is also found in the body and could indicate anemia. The retinol absorption may be due to the protein's diminution.

RBP4 is essential to recollect retinol from the retina, since it is an important nutrition for eye development. Its function in other tissues is still being investigated, and tissue-specific knockout mice can help to unravel new biological aspects. RBP4's potential roles go beyond transport, and so does the retinol binding mAb.

The recombinant RBP4 protein has inclusion bodies that have been precipitated. They should be renatured using a specific amount of urea to sustain its antigen-specific properties and activity. The presence of small amounts other proteins in the RBP4 protein may impact its capability to function as an immunegen. Our research showed that the RBP4 proteins had moderate antigen surface capability and flexibility regions.