RT Journal Article
SR Electronic
T1 Mutually exclusive expression of alternatively spliced FMRFamide transcripts in identified neuronal systems of the snail Lymnaea
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 2719
OP 2729
DO 10.1523/JNEUROSCI.13-06-02719.1993
VO 13
IS 6
A1 K Bright
A1 E Kellett
A1 SE Saunders
A1 M Brierley
A1 JF Burke
A1 PR Benjamin
YR 1993
UL http://www.jneurosci.org/content/13/6/2719.abstract
AB The FMRFamide gene of the snail Lymnaea encodes tetrapeptides (FMRFamide/FLRFamide) and heptapeptides (GDPFLRFamide/SDPFLRFamide) on separate exons. In situ hybridization probes specific to these exons were used to map the expression of the two exons in identified neuronal systems of the CNS. Analysis of more than 200 preparations showed that cytoplasmic expression of mRNA was exclusively of one type, with individual neurons expressing either the tetrapeptide or heptapeptide exon. Of the approximately 340 neurons expressing the two exons, the majority (80%) expressed the tetrapeptide exon. The tetrapeptide exon was more widespread, occurring in neurons from all 11 ganglia of the CNS. The heptapeptide was mainly confined to two ganglia (visceral and right parietal), with a small number of cells in three other ganglia. Mapping studies combined with dye marking of identified neurons showed the presence of the tetrapeptide exon in several behaviorally important networks: heart motoneurons, whole body withdrawal response motoneurons, and probably penis motoneurons as well as giant identified neurons (LP1, RPD1). The heptapeptides were prominent in two main clusters of cells (Bgp and Fgp) together with a smaller number of tetrapeptide-expressing cells.