We produced a global monthly dataset of temperature and salinity using data from Argo floats, Triangle Trans-Ocean Buoy Network (TRITON), and available conductivity-temperature-depth (CTD) casts. The Argo project started from 2000, and the number of floats is increasing yearly throughout the global ocean. The Argo floats observe pressure, temperature and salinity from the sea surface down to 2000 dbar and enable the production of monthly global datasets of temperature and salinity. We have created Grid Point Value of the Monthly Objective Analysis using Argo float data (MOAA GPV) that contains optimally interpolated temperature and salinity values at selected standard pressure levels on a 1˚ grid in the global ocean. The dataset is freely available on the Argo website of the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) at

A collagen‐like protein was identified from the otoliths of the chum salmon, Oncorhynchus keta. The otolith, composed mainly of calcium carbonate with small amount of organic matrices, is formed in the inner ear and serves as a part of the hearing and balance systems. Although the organic matrices may play important roles in the growth of otolith, little is known about their chemical nature and physiological function. In this study, a major organic component of the otolith, designated otolin‐1, which may serve as a template for calcification, was purified. The sequences of two tryptic peptides from otolin‐1 revealed high homology with parts of a saccular collagen which had been described previously [Davis, J.G., Oberholtzer, J.C., Burns, F.R. & Greene, M.I. (1995) Science267, 1031–1034]. Cloning of a cDNA coding for otolin‐1 revealed that the deduced amino‐acid sequence contained a collagenous domain in the central part of the protein. Although collagen is the most abundant structural protein in the animal body, otolin‐1 mRNA was expressed specifically in the sacculus. Immunohistochemical studies showed that otolin‐1 is synthesized in the transitional epithelium and transferred to the otolith and otolithic membrane. This is the first report concerning characterization of a structural protein containing many tandem repeats of the sequence, Gly‐Xaa‐Yaa, typical for collagen from the biomineral composed of calcium carbonate.

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In Crustacea, reproductive function and mechanisms regulating vitellogenesis have not been fully elucidated. This is due in great part to a lack of information concerning the biochemical nature of the vitellogenin molecule, the hemolymph precursor of yolk protein, vitellin, as well as the functional expression of the vitellogenin-encoding gene. We have therefore cloned a cDNA encoding vitellogenin in the kuruma prawn, Penaeus japonicus based on the N-terminal amino acid sequence of the 91 kDa subunit of vitellin. The open reading frame of this cDNA encoded 2,587 amino acid residues. This is the first investigation reporting a full-length cDNA and its corresponding amino acid sequence for vitellogenin in any crustacean species.Northern blot analysis and in situ hybridization have revealed that mRNA encoding vitellogenin was expressed in both the follicle cells in the ovary and the parenchymal cells in the hepatopancreas. In nonvitellogenic females, vitellogenin mRNA levels were negligible in both the ovary and hepatopancreas, but in vitellogenic females, levels were dramatically increased in both tissues. In the ovary, highest levels were observed during the early exogenous vitellogenic stage, and thereafter rapidly decreased, whereas in the hepatopancreas, high levels were maintained until the onset of the late vitellogenic stage. Differing profiles of vitellogenin mRNA levels in the ovary and hepatopancreas suggest that the contribution of these tissues to vitellogenin synthesis harbor separate and complementary roles during vitellogenesis.

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Molting in crustaceans is controlled by molt-inhibiting hormone (MIH) and ecdysteroids. It is presumed that MIH inhibits the synthesis and the secretion of ecdysteroids by the Y-organ, resulting in molt suppression. The amino acid sequence of MIH is similar to that of crustacean hyperglycemic hormone (CHH), and therefore, they form a peptide family referred to as the CHH family. Most of the CHH family peptides show no cross-activity, whereas a few peptides show multiple hormonal activities. To reveal the structural basis of this functional specificity, we determined the solution structure of MIH from the Kuruma prawn Marsupenaeus japonicus and compared the solution structure of MIH with a homology-modeled structure of M. japonicus CHH. The solution structure of MIH consisted of five ␣-helices and no ␤-structures, constituting a novel structural motif. The homology-modeled structure of M. japonicus CHH was very similar to the solution structure of MIH with the exception of the absence of the N-terminal ␣-helix and the C-terminal tail, which were sterically close to each other. The surface properties of MIH around this region were quite different from those of CHH. These results strongly suggest that this region is a functionally important site for conferring molt-inhibiting activity.Molting is one of the most significant processes occurring during the arthropod life cycle and is triggered by a molting hormone, ecdysteroids. In crustaceans, it is presumed that the synthesis and the secretion of ecdysteroids by the Y-organ are suppressed by molt-inhibiting hormone (MIH) 1 (1). MIH is produced by the X-organ and released from the sinus gland located in the eyestalk. Crustacean hyperglycemic hormone (CHH), gonad-inhibiting hormone, and mandibular organ-inhibiting hormone are also synthesized in and released from the X-organ/sinus gland complex. Most of these peptides consist of 72-78 amino acid residues and exhibit similar amino acid sequences. Therefore, these peptides form a peptide family referred to as the CHH family (2). The CHH family peptides commonly have six cysteine residues, which form three intramolecular disulfide bonds. Circular dichroism spectral analyses of some CHH family peptides demonstrated that they were rich in ␣-helices (3-5). However, there has so far been no report on the determination of the tertiary structure of any of the CHH family peptides.CHH family peptides show various biological activities: some peptides that suppress molting, increase hemolymph glucose levels, and suppress vitellogenesis in the ovary and others that suppress the synthesis of methyl farnesoate in the mandibular organ (2). In general, each CHH family peptide shows only one type of biological activity, although a few peptides show multiple hormonal activities. For instance, CHH from the American lobster Homarus americanus also exhibits molt-inhibiting activity (6), and mandibular organ-inhibiting hormone from the spider crab Libinia emarginata exhibits hyperglycemic activity (7).To reveal the structural basis of the fu...

A cDNA encoding vitellogenin (Vg) in the giant freshwater prawn, Macrobrachium rosenbergii, was cloned based on the cDNA sequence of vitellin (Vn) fragments A-N and B-42 determined previously, and its amino acid sequence deduced. The open reading frame (ORF) encoded 2,537 amino acid residues and its deduced amino acid sequence possessed three consensus cleavage sites, R-X-R-R, similar to those reported in Vgs of insects. The deduced primary structure of Vg in M. rosenbergii was seen to be similar to that of Penaeus japonicus, especially in the N-terminal region. It is therefore likely that Vgs in crustacean species including prawns and other related decapods exhibit a similar structural pattern. Based on the deduced primary structure of Vg and analysis of the various Vg and Vn subunits found in the hemolymph and ovary during ovarian maturation, we demonstrated the post-translational processing of Vg in M. rosenbergii. This is the first time that Vg processing has been clearly demonstrated in a crustacean species. Vg, after being synthesized in the hepatopancreas, is considered to be cleaved by a subtilisin-like endoprotease to form two subunits, A and proB, which are then released into the hemolymph. In the hemolymph, proB is possibly cleaved by a processing enzyme of unknown identity to give rise to subunits B and C/D. The three processed subunits A, B, and C/D are sequestered by the ovary to give rise to three yolk proteins, Macr-VnA, VnB, and VnC/D.