Leptin Rabbit E. coli

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.

Research topic

Energy metabolism and body weight regulation, Reproduction

Description

Leptin Rabbit Recombinant produced in E.coli is a single, non-glycosylated, polypeptide chain containing 146 amino acids and having a molecular mass of 16 kDa. The Leptin is purified by proprietary chromatographic techniques.

Amino Acid Sequence

Source

E. coli

Purity

Greater than 95.0% as determined by(a) Analysis by RP-HPLC. (b) Analysis by SDS-PAGE.

Biological Activity

Biological active as evidenced by inducing proliferation of BAF/3 cells stably transfected with the long form of human leptin receptor.

Formulation

The protein was lyophilized from a concentrated (1 mg/ml) solution with 0.0045 mM NaHCO₃.

Storage, Stability/Shelf Life

Lyophilized Leptin although stable at room temperature for 3 weeks, should be stored desiccated below –18°C. Upon reconstitution Leptin should be stored at 4°C between 2–7 days and for future use below –18°C. For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA). Please prevent freeze-thaw cycles.

Physical Appearance

Sterile filtered White lyophilized (freeze-dried) powder.

References

• 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) .
• 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.
• 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) .
• 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.
• 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) .
• 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) .
• 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.
• 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.
• 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) .

By research topic:

• Energy metabolism and body weight regulation
• Reproduction

By molecule:

• Leptin