DINeR

A Database for Insect Neuropeptide Research

Search the database for information about the various species and neuropeptides of interest

Insect Neuropeptides - Ion transport peptide

Introduction

The first Insect ITP was isolated and partially sequenced from Schistocerca gregaria (Audsley et al., 1992). This partial sequence was then used to clone the first gene encoding S. gregaria ITP (Meredith et al., 1996). The ITP gene encodes two types of peptides: a C-terminally amidated ITP (known as ITP) and a C-terminally unblocked peptide (known as ITP-like peptide, ITPL) (Dai et al., 2007; Dircksen, 2009). Insect ITPs along with crustacean CHH, MIH and MOIH form a family of structurally related peptides. ITP and its crustacean homologs contain 6 highly conserved cysteine residues (Webster et al., 2012). ITP and ITPL receptors were recently deorphanized in Bombyx mori (Nagai et al., 2014). BNGR-A2 (homologous to insect pyrokinin receptors) and BNGR-A34 (orphan receptor) were activated by ITP whereas BNGR-A24 was activated by ITPL. Surprisingly, BNGR-A24, which is homologous to insect tachykinin receptors, is activated by both ITPL and tachykinin (Nagai-Okatani et al., 2016).

Location

The cellular distribution of ITP and ITPL has been mapped in Manduca sexta, Drosophila melanogaster and Tribolium castaneum using a combination of immunohistochemistry and in situ hybridization (Begum et al., 2009; Dai et al., 2007; Dircksen et al., 2008; Drexler et al., 2007). In both the species, ITP is expressed in lateral neurosecretory cells. It has been suggested that ITP expression is confined to the CNS whereas ITPL is predominantly expressed in peripheral tissues.

Function

ITP was discovered based on its ability to modulate ion transport across the locust hindgut (Audsley et al., 1992; King et al., 1999). Thus, ITP may play a role as an anti-diuretic hormone in insects. In D. melanogaster ITP is expressed in a subset of clock neurons and plays a role in the clock output pathway (Hermann-Luibl et al., 2014; Johard et al., 2009). Lastly, knockdown of ITP in T. castaneum increases mortality during larval development and decreases egg production by adults (Begum et al., 2009).

SeqLogo and Cladogram

Click above image to go to SeqLogo and Cladogram page

Suggested Reviews

  • Dircksen, H., 2009. Insect ion transport peptides are derived from alternatively spliced genes and differentially expressed in the central and peripheral nervous system. J. Exp. Biol. 212, 401–412.
    View Review
  • Nässel, D.R., Winther, Å.M.E., 2010. Drosophila neuropeptides in regulation of physiology and behavior. Prog. Neurobiol. 92, 42–104. doi:10.1016/j.pneurobio.2010.04.010
    View Review
  • Webster, S.G., Keller, R., Dircksen, H., 2012. The CHH-superfamily of multifunctional peptide hormones controlling crustacean metabolism, osmoregulation, moulting, and reproduction. Gen. Comp. Endocrinol. 175, 217–233. doi:10.1016/j.ygcen.2011.11.035
    View Review

References

  • Audsley, N., McIntosh, C., Phillips, J.E., 1992. Isolation of a neuropeptide from locust corpus cardiacum which influences ileal transport. J. Exp. Biol. 173, 261–74.
  • Begum, K., Li, B., Beeman, R.W., Park, Y., 2009. Functions of ion transport peptide and ion transport peptide-like in the red flour beetle Tribolium castaneum. Insect Biochem. Mol. Biol. 39, 717–725. doi:10.1016/j.ibmb.2009.08.005
  • Dai, L., Zitnan, D., Adams, M.E., 2007. Strategic expression of ion transport peptide gene products in central and peripheral neurons of insects. J. Comp. Neurol. 500, 353–67. doi:10.1002/cne.21192
  • Dircksen, H., 2009. Insect ion transport peptides are derived from alternatively spliced genes and differentially expressed in the central and peripheral nervous system. J. Exp. Biol. 212, 401–412.
  • Dircksen, H., Tesfai, L.K., Albus, C., Nässel, D.R., 2008. Ion transport peptide splice forms in central and peripheral neurons throughout postembryogenesis of Drosophila melanogaster. J. Comp. Neurol. 509, 23–41. doi:10.1002/cne.21715
  • Drexler, A.L., Harris, C.C., dela Pena, M.G., Asuncion-Uchi, M., Chung, S., Webster, S., Fuse, M., 2007. Molecular characterization and cell-specific expression of an ion transport peptide in the tobacco hornworm, Manduca sexta. Cell Tissue Res. 329, 391–408. doi:10.1007/s00441-007-0391-9
  • Hermann-Luibl, C., Yoshii, T., Senthilan, P.R., Dircksen, H., Helfrich-Forster, C., 2014. The Ion Transport Peptide Is a New Functional Clock Neuropeptide in the Fruit Fly Drosophila melanogaster. J. Neurosci. 34, 9522–9536. doi:10.1523/JNEUROSCI.0111-14.2014
  • Johard, H.A.D., Yoishii, T., Dircksen, H., Cusumano, P., Rouyer, F., Helfrich-Förster, C., Nässel, D.R., 2009. Peptidergic clock neurons in Drosophila: Ion transport peptide and short neuropeptide F in subsets of dorsal and ventral lateral neurons. J. Comp. Neurol. 516, 59–73. doi:10.1002/cne.22099
  • King, D.., Meredith, J., Wang, Y.., Phillips, J.., 1999. Biological actions of synthetic locust ion transport peptide (ITP). Insect Biochem. Mol. Biol. 29, 11–18. doi:10.1016/S0965-1748(98)00098-8
  • Meredith, J., Ring, M., Macins, a, Marschall, J., Cheng, N.N., Theilmann, D., Brock, H.W., Phillips, J.E., 1996. Locust ion transport peptide (ITP): primary structure, cDNA and expression in a baculovirus system. J. Exp. Biol. 199, 1053–1061.
  • Nagai-Okatani, C., Nagasawa, H., Nagata, S., 2016. Tachykinin-Related Peptides Share a G Protein-Coupled Receptor with Ion Transport Peptide-Like in the Silkworm Bombyx mori. PLoS One 11, e0156501. doi:10.1371/journal.pone.0156501
  • Nagai, C., Mabashi-Asazuma, H., Nagasawa, H., Nagata, S., 2014. Identification and characterization of receptors for ion transport peptide (ITP) and ITP-like (ITPL) in the silkworm Bombyx mori. J. Biol. Chem. 289, 32166–77. doi:10.1074/jbc.M114.590646
  • Webster, S.G., Keller, R., Dircksen, H., 2012. The CHH-superfamily of multifunctional peptide hormones controlling crustacean metabolism, osmoregulation, moulting, and reproduction. Gen. Comp. Endocrinol. 175, 217–233. doi:10.1016/j.ygcen.2011.11.035