Tachykinin‐related peptide precursors in two cockroach species

Abstract

Tachykinins constitute a family of multifunctional neuropeptides whose signaling mechanisms seem to be partially conserved through evolution [1][2][3][4][5]. Although the tachykinin peptides display only limited sequence identities when comparing invertebrates and mammals, their G-protein-coupled receptors (GPCRs) display more striking similarities, suggesting ancestral relationships [4,5]. The three principal mammalian tachykinins, substance P, neurokinin A and neurokinin B, are processed from two precursors, preprotachykinin A and B and they act with preferential affinities on three different GPCRs, NK1-NK3 [5]. More recently, additional tachykinins, the hemokinins, were identified on a third precursor encoding gene, preprotachykinin C, expressed in hematopoietic cells of mouse, rat and humans [6,7].In invertebrates the tachykinins exist in two major forms: (a) the tachykinin-related peptides (TKRPs; previously termed TRPs) that differ from the mammalian tachykinins by having a C-terminus FXGXRamide (X ¼ variable residues), rather than FXGLMamide and (b) invertebrate tachykinins (Inv-TKs) with an

Direct peptide profiling of lateral cell groups of the antennal lobes of Manduca sexta reveals specific composition and changes in neuropeptide expression during development

“…Direct peptide profiling of nervous tissue or single cells in other insects revealed much higher signal intensities (e.g., Ma et al, 2000;Predel et al, 2005Predel et al, , 2006Berg et al, 2006). The low signal intensity appears thus to be an intrinsic property of M. sexta tissue, as also mass spectra obtained by direct profiling of neurohemal organs of M. sexta show lower signal intensities than those obtained from homologous organs of other insects (Predel et al, 2003;Predel, unpublished observations).…”

Molecular characterization and expression profiles of neuropeptide precursors in the migratory locust

“…Surprisingly, we also found that several neuropeptide precursors (Lom-NPF1a, Lom-NPF2, Lom-sNPF, Lom-TK, Lom-OK-B and Lom-NPP1) showed detectable expression levels in locust midgut. OK, TK and ITP are conserved brain-gut peptides, with functions including myotropic effects and regulation of ion and fluid transport (Audsley et al, 2013;Begum et al, 2009;Pascual et al, 2004;Predel et al, 2005). They may act as important factors to regulate peristalsis of digestive tract and food digestion in locust midgut.…”

Neuropeptides in interneurons of the insect brain

“…In D. melanogaster, more than 60 peptides may exist, and in the cockroach Periplaneta americana, more than 80 have been identified so far (see Predel et al 2005). Many of the peptides encoded on a given precursor display similar amino acid sequences.…”

“…In several cases, most or all of the predicted peptides are actually cleaved from the precursor. For example, five of the six tachykinin-related peptides (TKRPs) of the D. melanogaster precursor and all those of the cockroaches so far studied have been identified in brain tissue by mass spectrometry (Winther et al 2003;Predel et al 2005). Other precursors have been assayed in a similar fashion (see Baggerman et al 2002Baggerman et al , 2005Predel et al 2004a,b).…”

“…Many of the peptides encoded on a given precursor display similar amino acid sequences. For instance, 15 different isoforms of TKRPs have been found in the cockroach Leucophaea maderae and 23 FMRFamide-related peptides (FaRPs) in P. americana (Predel et al 2004a(Predel et al , 2005.…”