Ala(5)-galanin (2-11) is a GAL2R specific galanin analogue.
2016 (English)In: Neuropeptides, ISSN 0143-4179, E-ISSN 1532-2785, Vol. 60, 75-82 p.Article in journal (Refereed) Published
It is over 30years since the regulatory peptide galanin was discovered by Professor Mutt and co-workers. Galanin exerts its effects by binding to three galanin G-protein coupled receptors, namely GAL1R, GAL2R and GAL3R. Each galanin receptor has a different distribution in the central nervous system and the peripheral nervous system as well as distinctive signaling pathways, which implicates that the receptors are involved in different biological- and pathological effects. The delineation of the galaninergic system is however difficult due to a lack of stable, specific galanin receptor ligands. Herein, a new short GAL2R specific ligand, Ala(5)-galanin (2-11), is presented. The galanin (2-11) modified analogue Ala(5)-galanin (2-11) was tested in (125)I-galanin competitive binding studies for the three galanin receptors and the G-protein coupled receptor signaling properties was tested by the ability to influence second-messenger molecules like inositol phosphate and cyclic adenosine monophosphate. In addition, two different label-free real-time assays, namely EnSpire® based on an optical biosensor and xCELLigence® based on an electric biosensor, were used for evaluating the signaling properties using cell lines with different levels of receptor expression. Ala(5)-galanin (2-11) was subsequently found to be a full agonist for GAL2R with more than 375-fold preference for GAL2R compared to both GAL1R and GAL3R. The single amino acid substitution of serine to alanine at position 5 in the short ligand galanin (2-11) resulted in a ligand subsequently unable to bind neither GAL3R nor GAL1R, even at concentrations as high as 0.1mM.
Place, publisher, year, edition, pages
2016. Vol. 60, 75-82 p.
Agonist, Dynamic mass redistribution, Galanin, GAL2R specific ligand, GPCR, Impedance, Neuropeptide, Label-free real-time assay
Biochemistry and Molecular Biology
IdentifiersURN: urn:nbn:se:su:diva-136177DOI: 10.1016/j.npep.2016.08.008ISI: 000389398800011PubMedID: 27592409OAI: oai:DiVA.org:su-136177DiVA: diva2:1050820