title: Identification of allatostatins in the brown-winged green bug Plautia stali.
abstract: Juvenile hormone (JH) biosynthesis is inhibited under short-day conditions in the brown-winged green bug Plautia stali. We investigated allatostatic molecules in the brain of P. stali. Methanol brain extracts strongly inhibited JH biosynthesis. The allatostatic activities of the brain extracts were heat stable but gently suppressed by trypsin treatment, indicating that the allatostatic molecules were peptides. Grybi-MIP1, found in Gryllus bimaculatus as an allatostatic molecule, inhibited JH biosynthesis in P. stali. In contrast, peptides such as Dippu-AST2, 8, and 9, found in Diploptera punctata, did not affect JH biosynthesis in P. stali. We found a cDNA sequence encoding a peptide precursor of myoinhibitory peptides (MIPs), which we named Plast-MIP. Three synthetic peptides, AWKDLSKAW-NH2(Plast-MIP1), GWSDLQSAGW-NH2(Plast-MIP5), and AADWGSFRGSW-NH2(Plast-MIP8), deduced from the precursor sequence, showed clear inhibition of JH biosynthesis in P. stali. Analysis by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and tandem mass spectrometry showed that Plast-MIP8 resides in the brain. Expression of the Plast-MIP mRNA precursor was detected in the brain of insects reared under short- and long-day conditions. These results suggest that Plast-MIP is an allatostatic molecule and that MIPs are synthesized irrespective of photoperiod. To our knowledge, this is the first study to identify Plast-MIP as a functional allatostatin in hemipteran insects.
authors.affiliation: Department of Biology and Geosciences, Graduate School of Science, Osaka City University, Osaka 558-8585, Japan.
authors.forename: Keiji
authors.initials: K
authors.lastname: Matsumoto
authors.affiliation: Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Ohwashi 1-2, Tsukuba, 305-8634, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Suetsugu
authors.affiliation: Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Ohwashi 1-2, Tsukuba, 305-8634, Japan.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Tanaka
authors.affiliation: Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Ohwashi 1-2, Tsukuba, 305-8634, Japan.
authors.forename: Toyomi
authors.initials: T
authors.lastname: Kotaki
authors.affiliation: Department of Biology and Geosciences, Graduate School of Science, Osaka City University, Osaka 558-8585, Japan.
authors.forename: Shin G
authors.initials: SG
authors.lastname: Goto
authors.affiliation: Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Ohwashi 1-2, Tsukuba, 305-8634, Japan.
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Shinoda
authors.affiliation: Department of Biology and Geosciences, Graduate School of Science, Osaka City University, Osaka 558-8585, Japan. Electronic address: shigask@bio.sci.osaka-u.ac.jp.
authors.forename: Sakiko
authors.initials: S
authors.lastname: Shiga
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D005260:Female; D020062:Heteroptera / Q000235:genetics* / Q000378:metabolism; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D009479:Neuropeptides / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; D019476:Insect Proteins; D009479:Neuropeptides; D012333:RNA, Messenger; C076523:allatostatin
keywords: Corpus allatum; Diapause; Juvenile hormone; Myoinhibitory peptide; Photoperiodism; Radiochemical assay