title: Preparation of two recombinant crustacean hyperglycemic hormones from the giant freshwater prawn, Macrobrachium rosenbergii, and their hyperglycemic activities.
abstract: Crustacean hyperglycemic hormone (CHH) is released from the X-organ/sinus gland complex located in the eyestalks, and regulates glucose levels in the hemolymph. In the giant freshwater prawn (Macrobrachium rosenbergii), two cDNAs encoding different CHH molecules were previously cloned by other workers. One of these (Mar-CHH-2) was expressed only in the eyestalks, whereas the other (Mar-CHH-L) was expressed in the heart, gills, antennal gland, and thoracic ganglion, but not in the eyestalks. However, their biological activities had not yet been characterized. Therefore, in this study, recombinant Mar-CHH-2 (rMar-CHH-2) and Mar-CHH-L (rMar-CHH-L) were produced using an E. coli expression system, by expression in bacterial cells and recovery in the insoluble fraction. Thereafter, rMar-CHH-2 and rMar-CHH-L were subjected to refolding and were subsequently purified by reversed-phase HPLC. The rMar-CHH-2 and rMar-CHH-L thus obtained exhibited the same disulfide bond arrangements as those of other CHHs reported previously, indicative of natural conformation. In in vivo bioassay, rMar-CHH-2 showed significant hyperglycemic activity, whereas rMar-CHH-L had no effect. These results indicate that Mar-CHH-L does not function as a CHH, but may have some other, unknown function.
authors.affiliation: Japan International Research Center for Agricultural Sciences, Tsukuba, Ibaraki.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Ohira
authors.forename: Naoaki
authors.initials: N
authors.lastname: Tsutsui
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Nagasawa
authors.forename: Marcy N
authors.initials: MN
authors.lastname: Wilder
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D060829:Arthropod Proteins; D001681:Biological Assay; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004274:DNA, Recombinant / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D007447:Invertebrate Hormones; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D033541:Palaemonidae / Q000502:physiology*; D010957:Plasmids / Q000235:genetics; D017510:Protein Folding; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D060829:Arthropod Proteins; D004274:DNA, Recombinant; D007447:Invertebrate Hormones; D009419:Nerve Tissue Proteins; C015947:hyperglycemic hormone, crustacean