Identification of 26RFa, a hypothalamic neuropeptide of the RFamide peptide family with orexigenic activity.
A neuropeptide was isolated from a frog brain extract by HPLC purification and characterized by mass spectrometry. This 26-aa neuropeptide, which belongs to the RFamide peptide family, was designated 26RFa, and its primary structure was established as VGTALGSLAEELNGYNRKKGGFSFRF-NH2. Research in databases revealed the presence of sequences homologous to frog 26RFa in the human genome and in rat ESTs. On the basis of this sequence information, the cDNAs encoding the human and rat 26RFa precursors were cloned. The two preproteins show a similar organization, with the 26RFa sequence located in the C-terminal region of the precursor. Human preprotein (prepro)-26RFa encodes an additional putative RFamide peptide that is not found in the rat precursor. The primary structures of human, rat, and frog 26RFa exhibit approximately 80% identity, and the C-terminal octapeptide has been fully conserved from amphibians to mammals. In situ hybridization histochemistry revealed that, in the rat brain, the 26RFa gene is exclusively expressed in the ventromedial hypothalamic nucleus and in the lateral hypothalamic area. 26RFa induced a dose-dependent stimulation in cAMP production by rat pituitary cells in vitro and markedly increased food intake in mice. The conservation of the primary structure of 26RFa during vertebrate evolution, the discrete localization of the mRNA encoding its precursor in hypothalamic nuclei involved in the control of feeding behavior, and the observation that 26RFa possesses orexigenic properties indicate that this neuropeptide may play important biological functions.
Chartrel
Nicolas
N
European Institute for Peptide Research (IFRMP23), Laboratory of Cellular and Molecular Neuroendocrinology, Institut National de la Santé et de la Recherche Médicale, U 413, University of Rouen, 76821 Mont-Saint-Aignan, France.
Dujardin
Cynthia
C
Anouar
Youssef
Y
Leprince
Jérôme
J
Decker
Annick
A
Clerens
Stefan
S
Do-Régo
Jean-Claude
JC
Vandesande
Frans
F
Llorens-Cortes
Catherine
C
Costentin
Jean
J
Beauvillain
Jean-Claude
JC
Vaudry
Hubert
H
D000595:Amino Acid Sequence; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D000242:Cyclic AMP / Q000378:metabolism; D018076:DNA, Complementary / Q000378:metabolism; D019992:Databases as Topic; D004305:Dose-Response Relationship, Drug; D020224:Expressed Sequence Tags; D015894:Genome, Human; D006801:Humans; D007031:Hypothalamus / Q000378:metabolism; D017403:In Situ Hybridization; D008297:Male; D013058:Mass Spectrometry; D051379:Mice; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000737:chemistry*; D009479:Neuropeptides / Q000737:chemistry*; D010452:Peptide Biosynthesis; D010455:Peptides / Q000737:chemistry*; D012333:RNA, Messenger / Q000378:metabolism; D011898:Ranidae; D051381:Rats; D017208:Rats, Wistar; D017386:Sequence Homology, Amino Acid; D013997:Time Factors
D018076:DNA, Complementary; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; D010455:Peptides; C416987:RFamide peptide; D012333:RNA, Messenger; C480638:prepro-26RFa protein, human; C058047:arginylphenylalaninamide; D000242:Cyclic AMP