Behavioural data used in paper published in Scientific ReportsDataset for Fig. 4a: The results of the behavioural test of long-term memory (LTM) formation at 24 h after single-trial food reward classical conditioning. The data shown are difference scores calculated by subtracting the number of spontaneous feeding rasps counted in a two-minute period before the application of the conditioned stimulus from those counted in the two-minute period after the conditioned stimulus was applied.AbstractLong natural antisense transcripts (NATs) have been demonstrated in significant numbers in a variety of eukaryotic organisms. They are particularly prevalent in the nervous system suggesting their importance in neural functions. However, the precise physiological roles of the overwhelming majority of long NATs remain unclear. Here we report on the characterization of a novel molluscan nitric oxide synthase (NOS)-related long non-coding NAT (Lym-NOS1AS). This NAT is spliced and polyadenylated and is transcribed from the non-template strand of the Lym-NOS1 gene. We demonstrate that the Lym-NOS1AS is co-expressed with the sense Lym-NOS1 mRNA in a key neuron of memory network. Also, we report that the Lym-NOS1AS is spatially and temporally regulated by one-trial conditioning leading to long-term memory (LTM) formation. Specifically, in the cerebral, but not in the buccal ganglia, the temporal pattern of changes in Lym-NOS1AS expression after training correlates well with the alternation of memory lapse and non-lapse periods. Our data suggest that the Lym-NOS1AS plays a role in the consolidation of nitric oxide-dependent LTM.</p