Genomic organization of the FMRFamide gene in Lymnaea: multiple exons encoding novel neuropeptides.
Based on the sequencing of genomic and cDNA clones, we were able to determine that the FMRFamide gene consists of five exons covering at least 20 kb and predict the presence of further novel peptides. The exons are alternatively spliced: exon I (hydrophobic leader sequence) to exon II (tetrapeptides) and exon I to exons III (heptapeptides), IV, and V. A cDNA clone encoding the heptapeptides is described and has also been shown to encode further novel peptides SKPYMRFamide, HDYMRFamide, and SSFPRYamide. Analysis of the right internal parietal nerve using mass spectrometry showed that the novel peptide SKPYMRFamide was cleaved from the precursor. This peptide excites neurons, suggesting a physiological function in the CNS.
Kellett
E
E
Sussex Centre for Neuroscience, University of Sussex, Brighton, United Kingdom.
Saunders
S E
SE
Li
K W
KW
Staddon
J W
JW
Benjamin
P R
PR
Burke
J F
JF
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D004274:DNA, Recombinant; D005091:Exons; D019835:FMRFamide; D005796:Genes; D016678:Genome; D007447:Invertebrate Hormones / Q000235:genetics / Q000494:pharmacology; D008195:Lymnaea / Q000235:genetics*; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000235:genetics* / Q000494:pharmacology; D015345:Oligonucleotide Probes / Q000235:genetics; D014158:Transcription, Genetic
D018076:DNA, Complementary; D004274:DNA, Recombinant; D007447:Invertebrate Hormones; D009479:Neuropeptides; D015345:Oligonucleotide Probes; C067845:SDPFLRFamide; C077880:seryl-lysyl-prolyl-tyrosyl-methionyl-arginyl-phenylalaninamide; D019835:FMRFamide