Compound monograph
Galanin (human 1-30)
Galanin is a thirty-residue human neuropeptide acting through the galanin receptor family, and the reference ligand against which spexin's receptor selectivity is measured.
01
Identity & nomenclature
Galanin is a thirty-residue human neuropeptide acting through the galanin receptor family, and the reference ligand against which spexin's receptor selectivity is measured.
Human galanin is thirty residues with a free acid terminus and is NOT interchangeable with the 29-residue amidated galanins from other species that appear throughout this literature as comparators; length, C-terminal sequence and terminal chemistry all differ. Galanin-like peptide is a different molecule, not an alias. And spexin is not a proteolytic fragment of galanin — the two are separate gene products that happen to share receptors.
Canonical name: Galanin.
Declared aliases and development codes: GAL, Galanin(1-30).
02
Molecular properties
| Molecular formula | C139H210N42O43 |
|---|---|
| Molecular mass | 3157.4 Da |
| CAS Registry Number | 119418-04-1 |
| PubChem CID | 16133823 |
| One-letter sequence | GWTLNSAGYLLGPHAVGNHRSFSDKNGLTS |
Thirty residues with a FREE C-terminal carboxyl — not an amide. That distinguishes the human peptide from the 29-residue amidated galanins of several other species, which are widely used as comparators.
03
Structural characteristics
The cryo-EM study used galanin(1-30) and determined galanin-bound GALR1-Go and GALR2-Gq complexes, alongside a spexin-bound GALR2-Gq complex. The resolved galanin N-terminal region adopts a largely alpha-helical conformation in the extracellular vestibule, roughly parallel to the membrane. Its N-terminal residues 1-17 were well resolved; this does not establish structural detail for the entire human C-terminal segment. Functional measurements in the same study identified zinc as a negative allosteric regulator of GALR1 but not GALR2. The evolutionary comparison supplies family context; it does not establish a matched GALR3 potency comparison for this exact human thirty-residue free acid.
Terminal features: Free N-terminus, Free C-terminal carboxyl.
04
Molecular targets & mechanisms
05
Analytical considerations
Establish the human C-terminal sequence and the free acid at serine 30 specifically; conserved N-terminal coverage is the region shared with other species' galanins and cannot identify the human peptide. Look explicitly for amidated contaminants and for species substitutions against sequence-defined standards. Similar receptor activation does not distinguish human galanin from other active galanin sequences, and a generic galanin immunoassay may resolve neither length nor terminal processing.
06
Verified bibliography
- Structural insights into galanin receptor signaling.current
Jiang W, Zheng S
Proceedings of the National Academy of Sciences of the United States of America · 2022-05-20 · Journal Article
- Coevolution of the spexin/galanin/kisspeptin family: Spexin activates galanin receptor type II and III.current
Kim DK, Yun S, Son GH, Hwang JI, Park CR, Kim JI, Kim K, Vaudry H, Seong JY
Endocrinology · 2014-02-11 · Journal Article
10
Methodology & citation verification
Reference identity is checked against official PubMed metadata. Local deterministic receipts bind each normalized title and canonical metadata record to its verification date. Scientific values remain absent when an authoritative source has not been verified.
Read the full methodology →