Recombinant Human GHRL Protein: Properties & Research Uses

Recombinant Human GHRL Protein is a biologically relevant research reagent representing the mature form of human ghrelin, a key peptide hormone involved in appetite stimulation, growth hormone secretion, and energy homeostasis.

Product Name

Recombinant Human GHRL Protein

SKU

rp369354

Gene / Protein Target

GHRL (Ghrelin / Obestatin Prepropeptide)

Primary Biological Function

Appetite stimulation, growth hormone secretagogue activity, energy homeostasis regulation

Receptor Target

Growth Hormone Secretagogue Receptor (GHSR / GHS-R1a)

Research Areas

Metabolism, obesity, endocrinology, appetite regulation, cardiovascular biology

Supplier Reference

absea#PQ-968

Biological Background of GHRL (Ghrelin)

Ghrelin, encoded by the GHRL gene, is a 28-amino-acid peptide hormone predominantly produced by X/A-like enteroendocrine cells in the gastric fundus. It is synthesized as a 117-amino-acid prepropeptide (preproghrelin) that undergoes proteolytic processing to yield the mature ghrelin peptide.

A defining feature of ghrelin is its unique post-translational modification: octanoylation at Ser3, catalyzed by Ghrelin O-Acyltransferase (GOAT). This acylation is essential for binding to and activating the Growth Hormone Secretagogue Receptor (GHS-R1a / GHSR), mediating the hormone's primary endocrine and neuroendocrine effects. Des-acyl ghrelin (unacylated ghrelin) also circulates at higher concentrations and exerts distinct, receptor-independent biological activities.

The GHRL gene also encodes obestatin, a separate peptide derived from the C-terminal portion of preproghrelin, although its physiological role remains an area of active investigation.

Key Properties of Recombinant Human GHRL Protein

Recombinant Human GHRL Protein (SKU: rp369354) is produced to support reproducible in vitro and in vivo research. Key physicochemical and functional considerations include:

• Origin: Human GHRL sequence, recombinantly expressed to reflect the mature, biologically active form of the peptide.
• Acylation status: Researchers should confirm whether the recombinant preparation is acylated (active ghrelin) or unacylated (des-acyl ghrelin), as this fundamentally determines receptor binding capacity and downstream signaling. Verify with current product datasheet.
• Purity: Recombinant ghrelin preparations are typically manufactured to high purity (commonly >95% by SDS-PAGE or HPLC) to minimize endotoxin interference and non-specific effects in cell-based assays.
• Formulation: Typically supplied lyophilized or in aqueous buffer. Consult the current Certificate of Analysis (CoA) for lot-specific formulation, reconstitution instructions, and storage conditions.
• Biological Activity: Functional activity should be confirmed by bioassay, such as stimulation of GH release from pituitary cells or activation of GHSR signaling pathways (e.g., calcium flux, ERK phosphorylation).

Note: Always refer to the product-specific datasheet and CoA for definitive specifications, as these may vary by lot.

Research Applications

Recombinant Human GHRL Protein is employed across a broad range of research contexts:

• Appetite and Energy Metabolism: Ghrelin is the only known orexigenic (appetite-stimulating) circulating hormone. Recombinant GHRL protein is used to model pre-prandial hunger states, study hypothalamic feeding circuits (including NPY/AgRP neuronal activation), and investigate energy expenditure regulation.
• Growth Hormone (GH) Axis Studies: As a potent GH secretagogue, recombinant ghrelin is used in cell-based assays and animal models to study GH release from pituitary somatotrophs and downstream IGF-1 signaling.
• Obesity and Metabolic Disease Research: Ghrelin levels are altered in obesity, anorexia nervosa, and type 2 diabetes. Recombinant GHRL protein enables mechanistic studies of these disease states and supports drug target validation for metabolic disorders.
• Cardiovascular Biology: Ghrelin has reported cardioprotective and vasodilatory effects. Recombinant protein is used in cardiac cell and endothelial cell models to explore these actions.
• Receptor Pharmacology: Used in GHSR binding assays, competitive displacement studies, and downstream signaling pathway characterization (Gq/G11, cAMP, MAPK pathways).
• Assay Development and Standard Curves: High-purity recombinant GHRL protein serves as a reference standard for ELISA, radioimmunoassay (RIA), and other immunoassay platforms.

Handling, Reconstitution & Storage Guidelines

Proper handling of Recombinant Human GHRL Protein is essential to preserve biological activity and experimental reproducibility. General best-practice guidelines include:

• Reconstitution: Reconstitute lyophilized protein in sterile, carrier protein-containing buffer (e.g., PBS with 0.1% BSA) as recommended in the product datasheet. Avoid vigorous vortexing; gently pipette to mix.
• Aliquoting: Upon reconstitution, prepare single-use aliquots to minimize freeze-thaw cycles, which can degrade peptide integrity and reduce biological activity.
• Storage: Lyophilized protein should typically be stored at -20°C or -80°C. Reconstituted protein should be stored at -80°C and used promptly. Consult the CoA for lot-specific recommendations.
• Acylation sensitivity: The octanoyl modification on acylated ghrelin is susceptible to hydrolysis under alkaline conditions and by serum esterases. Maintain appropriate pH and use protease inhibitor cocktails in biological samples.
• Endotoxin testing: Confirm endotoxin levels (LAL assay) from the CoA before use in cell-based or in vivo studies to avoid confounding inflammatory responses.

Always refer to the product-specific datasheet and CoA provided with each lot for authoritative handling instructions.

Why Choose Aladdin Scientific Recombinant Human GHRL Protein

Aladdin Scientific's Recombinant Human GHRL Protein (rp369354) is supplied to meet the demanding requirements of modern biomedical research:

• Quality Assurance: Each lot is subject to quality control testing, with results documented in a Certificate of Analysis (CoA) available upon request.
• Research-Grade Purity: Manufactured to high-purity standards suitable for sensitive cell-based assays, binding studies, and in vivo experiments.
• Reliable Supply: Consistent availability supports longitudinal studies and large-scale screening campaigns.
• Technical Support: Aladdin Scientific's technical team is available to advise on reconstitution, application optimization, and assay design for GHRL-related research.
• Competitive Pricing: Designed to provide value without compromising on quality for academic, biotech, and pharmaceutical research environments.

For ordering, technical documentation, or application-specific guidance, contact Aladdin Scientific directly or visit the product page for SKU rp369354.

Frequently asked questions

What is the difference between acylated and des-acyl ghrelin, and which form is rp369354?

Acylated ghrelin carries an octanoyl group at Ser3, which is essential for binding and activating the GHSR receptor to stimulate growth hormone release and appetite. Des-acyl (unacylated) ghrelin lacks this modification and does not activate GHSR but has distinct biological activities. Please consult the product datasheet and Certificate of Analysis for rp369354 to confirm the acylation status of the specific lot you receive.

How should I reconstitute and store Recombinant Human GHRL Protein (rp369354)?

Lyophilized recombinant ghrelin protein should be reconstituted in sterile buffer, typically PBS containing a carrier protein such as 0.1% BSA, following the instructions in the product datasheet. After reconstitution, aliquot into single-use volumes and store at -80°C to minimize freeze-thaw degradation. Always verify lot-specific storage recommendations in the Certificate of Analysis.

What are the primary research applications for Recombinant Human GHRL Protein?

Recombinant Human GHRL Protein is primarily used in studies of appetite regulation and energy homeostasis, growth hormone secretion, obesity and metabolic disease mechanisms, cardiovascular biology, and GHSR receptor pharmacology. It also serves as a reference standard for immunoassays such as ELISA and radioimmunoassay.

How do I confirm the biological activity of rp369354 in my assay?

Biological activity of recombinant ghrelin can be assessed using cell-based functional assays such as measuring calcium flux in GHSR-expressing cells, monitoring ERK or Akt phosphorylation, or quantifying GH release from primary pituitary cells or pituitary cell lines. Refer to the product datasheet for activity specifications and recommended assay conditions provided by the manufacturer.

Is Recombinant Human GHRL Protein suitable for in vivo animal studies?

Recombinant Human GHRL Protein can be used in in vivo studies, but researchers must verify endotoxin levels (confirmed by LAL assay in the CoA), purity, and formulation suitability prior to administration. Confirm that the product specifications meet the requirements of your specific animal study protocol and institutional guidelines.

References

1. Kojima M, Hosoda H, Date Y, Nakazato M, Matsuo H, Kangawa K. Ghrelin is a growth-hormone-releasing acylated peptide from stomach. Nature. 1999;402(6762):656-660. doi:10.1038/45230
2. Müller TD, Nogueiras R, Andermann ML, et al. Ghrelin. Molecular Metabolism. 2015;4(6):437-460. doi:10.1016/j.molmet.2015.03.005
3. Gutierrez JA, Solenberg PJ, Perkins DR, et al. Ghrelin octanoylation mediated by an orphan lipid transferase. Proceedings of the National Academy of Sciences. 2008;105(17):6320-6325. doi:10.1073/pnas.0800708105
4. Davenport AP, Bonner TI, Foord SM, et al. International Union of Pharmacology. LVI. Ghrelin receptor nomenclature, distribution, and function. Pharmacological Reviews. 2005;57(4):541-546. doi:10.1124/pr.57.4.1

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.