[Ala13]-Apelin-13

Product Name: [Ala13]-Apelin-13

Sequence One Letter Code: QRPRLSHKGPMPA

Sequence Three Letter Code: H-Gln-Arg-Pro-Arg-Leu-Ser-His-Lys-Gly-Pro-Met-Pro-Ala-OH

Cas No: 568565-11-7

Chemical Formula:C63H107N23O16S

Molecular Weight: 1474.8

Purity: 95%

Form: Lyophilized

Storage Conditions: - 20 °C

Research Area: Cardiovascular Disease Research

SMILES: C[C@@H](C(=O)O)NC(=O)[C@@H]1CCCN1C(=O)[C@H](CCSC)NC(=O)[C@@H]2CCCN2C(=O)CNC(=O)[C@H](CCCCN)NC(=O)[C@H](CC3=CN=CN3)NC(=O)[C@H](CO)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CCCN=C(N)N)NC(=O)[C@@H]4CCCN4C(=O)[C@H](CCCN=C(N)N)NC(=O)[C@H](CCC(=O)N)N

IUPAC: (2S)-2-[[(2S)-1-[(2S)-2-[[(2S)-1-[2-[[(2S)-6-amino-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-5-(diaminomethylideneamino)-2-[[(2S)-1-[(2S)-5-(diaminomethylideneamino)-2-[[(2S)-2,5-diamino-5-oxopentanoyl]amino]pentanoyl]pyrrolidine-2-carbonyl]amino]pentanoyl]amino]-4-methylpentanoyl]amino]-3-hydroxypropanoyl]amino]-3-(1H-imidazol-5-yl)propanoyl]amino]hexanoyl]amino]acetyl]pyrrolidine-2-carbonyl]amino]-4-methylsulfanylbutanoyl]pyrrolidine-2-carbonyl]amino]propanoic acid

INCHIKEY: PZJZONZEQDOQAZ-COFPHXSQSA-N

INCHI:

InChI=1S/C63H107N23O16S/c1-34(2)28-42(81-52(92)39(13-7-22-72-62(67)68)78-58(98)47-17-11-26-86(47)59(99)40(14-8-23-73-63(69)70)79-50(90)37(65)18-19-48(66)88)53(93)83-44(32-87)55(95)82-43(29-36-30-71-33-75-36)54(94)77-38(12-5-6-21-64)51(91)74-31-49(89)84-24-9-15-45(84)57(97)80-41(20-27-103-4)60(100)85-25-10-16-46(85)56(96)76-35(3)61(101)102/h30,33-35,37-47,87H,5-29,31-32,64-65H2,1-4H3,(H2,66,88)(H,71,75)(H,74,91)(H,76,96)(H,77,94)(H,78,98)(H,79,90)(H,80,97)(H,81,92)(H,82,95)(H,83,93)(H,101,102)(H4,67,68,72)(H4,69,70,73)/t35-,37-,38-,39-,40-,41-,42-,43-,44-,45-,46-,47-/m0/s1

Source / Species: human, mouse, bovine, rat

Conjugation: Unconjugated

Code Nacres: NA.26

Application: [Ala13]-Apelin-13 is a synthetic analog of the endogenous peptide apelin-13 in which the amino acid at position 13 is substituted with alanine. Apelin peptides function as endogenous ligands for the APJ receptor (also known as the apelin receptor), a class A G protein–coupled receptor involved in the regulation of cardiovascular function, fluid balance, and metabolic processes. Apelin-13 is recognized as one of the most potent biologically active fragments of the apelin precursor and exhibits strong inotropic and vasoactive effects that influence cardiac contractility and vascular tone. The [Ala13]-Apelin-13 variant is widely used in research to investigate structure–activity relationships within the apelin peptide family, as well as receptor binding and downstream signaling pathways associated with APJ activation. This peptide is particularly valuable in studies exploring cardiovascular physiology, vascular regulation, and metabolic disease mechanisms.

Current Research: The apelin peptide system has emerged as an important regulatory network involved in cardiovascular physiology, fluid homeostasis, and metabolic regulation. Central to this system is apelin, an endogenous peptide ligand that binds to the APJ receptor (also known as the apelin receptor or APLNR), a class A G protein–coupled receptor (GPCR). Among the various apelin fragments generated from the apelin precursor protein, apelin-13 is considered one of the most biologically potent and widely studied forms. To better understand how structural changes influence apelin receptor activation, researchers have developed modified peptide analogs such as [Ala13]-Apelin-13, a synthetic variant in which the amino acid at position 13 is replaced with alanine. This modification provides a valuable experimental model for investigating structure–activity relationships, receptor binding characteristics, and downstream signaling pathways associated with APJ receptor activation. The Apelin–APJ Signaling System The apelinergic system consists primarily of the apelin peptides and the APJ receptor, which is expressed in multiple tissues including the heart, vascular endothelium, brain, adipose tissue, and kidneys. Activation of APJ by endogenous apelin peptides triggers intracellular signaling cascades mediated through G proteins and β-arrestin pathways. These signaling events influence a wide range of physiological functions, including: Regulation of cardiac contractility Control of vascular tone Maintenance of fluid and electrolyte balance Modulation of energy metabolism Because of its widespread physiological roles, the apelin–APJ pathway has become an important focus of research in fields such as cardiovascular biology, metabolic disease, and vascular physiology. Apelin-13: A Potent Bioactive Fragment Apelin is synthesized as a larger precursor peptide that undergoes enzymatic processing to generate several active fragments, including apelin-36, apelin-17, and apelin-13. Among these, apelin-13 is often regarded as one of the most potent and biologically active forms. Experimental studies have shown that apelin-13 produces strong physiological effects, particularly within the cardiovascular system. Key reported activities include: Positive inotropic effects, increasing cardiac contractile force Vasodilation, which influences blood vessel diameter and blood pressure Endothelial signaling modulation, affecting vascular function These effects highlight the importance of apelin-13 in maintaining cardiovascular homeostasis and circulatory regulation. Structural Modification in [Ala13]-Apelin-13 [Ala13]-Apelin-13 is a synthetic analog designed to explore how changes in peptide structure affect receptor activity. In this variant, the thirteenth amino acid residue is substituted with alanine, creating a slightly altered peptide sequence compared with native apelin-13. Such modifications are commonly used in peptide research to evaluate how individual amino acids contribute to: Receptor binding affinity Peptide stability Signal transduction efficiency Functional selectivity in GPCR signaling By comparing the biological responses generated by apelin-13 and its analogs, scientists can better understand which structural elements are critical for effective APJ receptor activation. Investigating Structure–Activity Relationships Structure–activity relationship (SAR) studies play a crucial role in peptide pharmacology and receptor biology. The [Ala13]-Apelin-13 analog provides a controlled experimental model that allows researchers to investigate how the C-terminal region of apelin peptides influences receptor interaction. Through biochemical and cellular assays, scientists can examine how this substitution affects: APJ receptor binding dynamics G protein signaling activation β-arrestin recruitment pathways Intracellular signaling cascades such as ERK or PI3K pathways These studies contribute to a deeper understanding of ligand–receptor interactions within the apelinergic system, helping clarify the molecular determinants that govern GPCR activation. Relevance to Cardiovascular and Metabolic Research Because the apelin–APJ axis is strongly linked to cardiovascular physiology, modified peptides like [Ala13]-Apelin-13 are frequently used in studies examining heart function and vascular regulation. Research involving apelin peptides has explored their roles in: Cardiac output regulation Blood vessel dilation and endothelial function Fluid balance and renal physiology Metabolic processes including glucose utilization and lipid metabolism In addition, the apelinergic system has been investigated in relation to metabolic disorders and cardiovascular diseases, where alterations in apelin signaling may influence disease progression. A Versatile Peptide for Experimental Applications [Ala13]-Apelin-13 has become a valuable tool in experimental biology due to its ability to help dissect specific structural and functional features of apelin signaling. By using this analog in controlled laboratory settings, researchers can explore: The structural determinants of apelin receptor activation Functional differences between natural and modified ligands Signaling pathway specificity within GPCR networks Mechanisms underlying cardiovascular and metabolic regulation These investigations provide important insights into the broader peptide signaling landscape that governs physiological homeostasis. Conclusion [Ala13]-Apelin-13 represents a strategically modified peptide that enables detailed exploration of the apelin–APJ receptor signaling system. Through substitution of the terminal amino acid with alanine, this analog serves as a useful model for studying structure–activity relationships and ligand–receptor interactions within the apelin peptide family. As research into the apelinergic pathway continues to expand, peptides like [Ala13]-Apelin-13 remain essential tools for advancing scientific understanding of cardiovascular function, vascular signaling, and metabolic regulation.