Identification of the first neuropeptides from the CNS of Hemiptera: CAPA peptides of the southern green stinkbug Nezara viridula (L.) Reinhard Predel a,c, *, William K. Russell b , Susanne Neupert c , David H. Russell b , Jesus F. Esquivel a , Ronald J. Nachman a, ** a Areawide Pest Management Research, Southern Plains Agricultural Research Center, USDA, 2881 F/B Road, College Station, TX 77845, USA b The Laboratory for Biological Mass Spectrometry, Department of Chemistry, Texas A&M University, College Station, TX 77843, USA c Institute of General Zoology, Friedrich-Schiller-University, Erbertstrasse 1, Jena 07743, Germany 1. Introduction Hemipteran insects are obligate liquid feeders which possess highly specialized morphological and physiological adaptations to optimize their food intake strategy. Both, blood-feeding and plant-feeding species exist which comprise a large number of economically important pest insects which may transmit Chagas disease or cause considerable damage on crop species every year. One of the important adaptations is their ability to cope with a temporary excess of water. This regulation of diuretic processes is particularly well investigated in the blood- feeding Rhodnius prolixus which serves as a model insect for studying the water balance in Hemiptera [8,19,25]. It is well established that neuropeptides are key factors in controlling primary urine production in Malpighian tubules (CRF-like peptides, insect kinins, CAPA peptides) and fluid reabsorption from the hindgut (ion transport peptide ITP)(see [1,25]). However, none of these neuropeptides have so far been peptides 27 (2006) 2670–2677 article info Article history: Received 31 March 2006 Received in revised form 10 May 2006 Accepted 11 May 2006 Published on line 7 July 2006 Keywords: CAPA gene Periviscerokinin Pyrokinin FXPRLamide CAP2b Perisympathetic organs Mass spectrometry Insect neuropeptide abstract A direct mass spectrometric investigation of nerve homologs of the abdominal perisympa- thetic organs was employed to reveal the first and complete sequences of CAPA peptides from a hemipteran species, the southern green stinkbug Nezara viridula. Side-chain frag- mentations allowed the assignment of internal Leu/Ile; on-plate acetylation was used to distinguish between the mass-related Lys and Gln. The following sequences were obtained: DQLFPFPRV-NH 2 (CAPA-PVK-1), EQLIPFPRV-NH 2 (CAPA-PVK-2), and NGSAGNGGLWFGPRL/I- NH 2 (CAPA-PK). CAPA-PVKs are associated with the regulation of diuresis in insects, and identification of those native to a hemipteran will provide the experimental basis to better understand regulation of water balance in this family of insects. Published by Elsevier Inc. * Corresponding author. Tel.: +49 3641 9 49191; fax: +49 3641 9 49192. ** Corresponding author. Tel.: +1 979 260 9315; fax: +1 979 260 9377. E-mail addresses: b6prre@pan.zoo.uni-jena.de (R. Predel), nachman@tamu.edu (R.J. Nachman). available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/peptides 0196-9781/$ – see front matter . Published by Elsevier Inc. doi:10.1016/j.peptides.2006.05.013