Leptin Human (E. coli)

Description

The AA sequence of recombinant Human Leptin is corresponding to the AA sequence of human serum leptin.

Amino Acid Sequence

Source

E. coli

Purity

>95%

SDS-PAGE gel

12% SDS-PAGE separation of Human Leptin 1. M.W. marker – 14, 21, 31, 45, 66, 97 kDa 2. reduced and heated sample, 7μg/lane 3. non-reduced and non-heated sample, 7μg/lane

Formulation

Filtered (0,4 μm) and lyophilized in 0.5 mg/mL in 10 mM sodium citrate, pH 4.0

Reconstitution

Add 0.1M Acetate buffer pH4 to prepare a working stock solution of approximately 0.5 mg/mL and let the lyophilized pellet dissolve completely. For conversion into higher pH value, we recommend intensive dilution by relevant buffer to a concentration of 10μg/mL. In higher concentrations the solubility of this antigen is limited. Product is not sterile! Please filter the product by an appropriate sterile filter before using it in the cell culture.

Storage, Stability/Shelf Life

Store lyophilized protein at –20°C. Lyophilized protein remains stable until the expiry date when stored at –20°C. Aliquot reconstituted protein to avoid repeated freezing/thawing cycles and store at –80°C for long term storage. Reconstituted protein can be stored at 4°C for a limited period of time; it does not show any change after two weeks at 4°C.

Quality Control Test

BCA to determine quantity of the protein.

SDS PAGE to determine purity of the protein.

Applications

ELISA, Western blotting

Note

This product is intended for research use only.

Introduction to the Molecule

Leptin, the product of the ob (obese) gene, is a single-chain 16 kDa proteohormone consisting of 146 amino acid residues. Leptin is produced by differentiated adiocytes, although production have been demonstrated in other tissues, such as fundus of the stomach, the sceletal muscle, the liver, and the placenta. Leptin is considered to play an important role in appetite control, fat metabolism and body weight regulation. It targets the central nervous system, in particular the hypothalamus, suppressing food intake and stimulating energy expenditure. In humans, leptin levels correlate with body mass index (BMI) and percentage body fat, and are elevated even in obese individuals. Leptin has a dual action; it decreases the appetite and increases energy consumption, causing more fat to be burned.

References to this Product

• Stejskal D, Karpisek M . Adipocyte fatty acid binding protein in a Caucasian population: a new marker of metabolic syndrome?. Eur J Clin Invest . Sep;36(9):621-5 (2006)
• Nonaka S, Hashizume T, Yamashita T . Effects of leptin and leptin peptide amide on the release of luteinizing hormone, growth hormone and prolactin from cultured porcine anterior pituitary cells. Animal Science Journal . 77, 44-52 (2006)
• Johnstone AM, Murison SD, Duncan JS, Rance KA, Speakman, JR . Factors influencing variation in basal metabolic rate include fat-free mass, fat mass, age, and circulating thyroxine but not sex, circulating leptin, or triiodothyronine. Am J Clin Nutr . Nov;82(5):941-8 (2005)
• Matarese G, Carrieri PB, La Cava A, Perna F, Sanna V, De Rosa V, Aufiero D, Fontana S, Zappacosta S . Leptin increase in multiple sclerosis associates with reduced number of CD4(+)CD25+ regulatory T cells. Proc Natl Acad Sci U S A . Apr 5;102(14):5150-5 (2005)
• Lee MJ, Fried SK . Multilevel regulation of leptin storage, turnover, and secretion by feeding and insulin in rat adipose tissue. J Lipid Res . Sep;47(9):1984-93 (2006)

References

• Ricci M.R., Lee M.J., et al. Isoproterenol decreases leptin release from rat and human adipose tissue through posttranscriptional mechanisms. Am. J. Physiol. Endocrinol. Metab. 2005; (288), E798-E804.
• Maffei M., Halaas J., Ravussin E. et al. Leptin levels in human and rodent: measurement of plasma leptin and ob RNA in obese and weight reduced subjects. Nature Med. 1995; 1155 1161.
• Maffei M., Halaas J., Ravussin E. et al. Leptin levels in human and rodent: measurement of plasma leptin and ob RNA in obese and weight-reduced subjects. Nature Med. 1, 1155-1161 (1995) .
• Lonnqvist F., Arner P., Nordfors L. and Shalling M. Overexpression of the obese (ob) gene in adipose tissue of human subjects. Nature Med. 1, 950-953 (1995) .
• Zhang Y., Proenca R., Maffei M., Barone M., Leopold L., Friedman J. Positional Cloning of the Mouse Obese Gene and its Human Homologue. Nature 372, 425-432 (1994) .
• Considine R.V., Sinha M.K., Heiman M.L. et al. Serum immunoreactive leptin concentrations in normal weight and obese humans. N. Engl. J. Med. 1996; (334), 292 295.
• Considine R.V., Sinha M.K., Heiman M.L. et al. Serum immunoreactive leptin concentrations in normal-weight and obese humans. N. Engl. J. Med. 334, 292-295 (1996) .
• Halaas J.L., Gajiwala K.S., Maffei M. et al. Weight reducing effects of the plasma protein encoded by the obese gene. Science 1995; (269), 543 546.
• Halaas J.L., Gajiwala K.S., Maffei M. et al. Weight-reducing effects of the plasma protein encoded by the obese gene. Science 269, 543-546 (1995) .