Myomodulin gene of Lymnaea: structure, expression, and analysis of neuropeptides.
The myomodulin family of neuropeptides is an important group of neural cotransmitters in molluscs and is known to be present in the neural network that controls feeding behavior in the snail Lymnaea. Here we show that a single gene encodes five structurally similar forms of myomodulin: GLQMLRLamide, QIPMLRLamide, SMSMLRLamide, SLSMLRLamide, and PMSMLRLamide, the latter being present in nine copies. Analysis of the organization of the gene indicates that it is transcribed as a single spliced transcript from an upstream promoter region that contains multiple cAMP-responsive elements, as well as putative elements with homology to tissue-specific promoter-binding sites. The presence in nervous tissue of two of the peptides, GLQMLRLamide and PMSMLRLamide, is confirmed by mass spectrometry. In situ hybridization analysis indicates that the gene is expressed in specific cells in all ganglia of the CNS of Lymnaea, which will allow physiological analysis of the function of myomodulins at the level of single identified neurons.
Kellett
E
E
Sussex Centre for Neuroscience, School of Biological Sciences, University of Sussex, Falmer, Brighton, United Kingdom.
Perry
S J
SJ
Santama
N
N
Worster
B M
BM
Benjamin
P R
PR
Burke
J F
JF
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002490:Central Nervous System / Q000502:physiology; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D015870:Gene Expression; D005796:Genes; D016678:Genome; D008195:Lymnaea / Q000235:genetics*; D008969:Molecular Sequence Data; D009417:Nerve Tissue / Q000378:metabolism; D009479:Neuropeptides / Q000235:genetics* / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D011498:Protein Precursors / Q000235:genetics; D014158:Transcription, Genetic
D018076:DNA, Complementary; D009479:Neuropeptides; D011498:Protein Precursors; C053302:myomodulin