BrachyuraPandalidaeGanglia, InvertebrateXenopusRNA, Ribosomal, 5SPylorusAchilleaNeuropeptidesTranscription Factor TFIIIABalaenopteraDNA, RibosomalAcidobacteriaCrustaceaTachykininsDigestive SystemPeriodicityRNA, RibosomalSpectrometry, Mass, Matrix-Assisted Laser Desorption-IonizationSpecies SpecificityStomachXenopus laevisMolecular Sequence DataNucleosomesBase SequencePhylogenyOligopeptidesGenesNeurotransmitter AgentsOocytesNerve NetHistonesDNATranscription, GeneticDNA Restriction EnzymesMotor NeuronsAmino Acid SequenceCloning, MolecularNeuronsAction Potentials