title: Structure-activity studies on adipokinetic hormones in Manduca sexta.
abstract: Structure-activity studies were performed for adipokinetic hormone (AKH) in Manduca sexta. Seven naturally occurring and four synthetic peptides of the red pigment concentrating hormone (RPCH)/AKH family were tested in larvae of M. sexta for activation of glycogen phosphorylase in fat body. pGlu at the N-terminal was found to be important for activity of peptides; however, Manduca AcGly1AKH is partially active. The amino acids at all positions appear to be of importance for activity, with the possible exception of the two serine residues in positions six and seven. Generally, the more amino acids are exchanged, the less the peptide will bind to the receptor. In M. sexta a beta-bend appears not to be important for the binding of peptides. Peptides ten amino acids long appear to be more active than shorter ones.
authors.affiliation: Department of Biochemistry, University of Arizona, Tucson 85721.
authors.forename: R
authors.initials: R
authors.lastname: Ziegler
authors.forename: K
authors.initials: K
authors.lastname: Eckart
authors.forename: R D
authors.initials: RD
authors.lastname: Jasensky
authors.forename: J H
authors.initials: JH
authors.lastname: Law
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004789:Enzyme Activation / Q000187:drug effects; D005216:Fat Body / Q000187:drug effects / Q000201:enzymology; D007301:Insect Hormones / Q000737:chemistry* / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects / Q000201:enzymology; D008969:Molecular Sequence Data; D009036:Moths / Q000187:drug effects* / Q000201:enzymology; D009842:Oligopeptides / Q000737:chemistry* / Q000494:pharmacology*; D006005:Phosphorylases / Q000378:metabolism; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives; D013329:Structure-Activity Relationship
chemical_list: D007301:Insect Hormones; D009842:Oligopeptides; C044833:adipokinetic hormone; D006005:Phosphorylases; D011761:Pyrrolidonecarboxylic Acid