The ex vivo effects of eyestalk peptides on ovarian vitellogenin gene expression in the kuruma prawn Marsupenaeus japonicus

Isolation of crustacean hyperglycemic hormone-family peptides with vitellogenesis-inhibiting activity from the shiba shrimp Metapenaeus joyneri

“…This result is consistent with previous studies in which all type I peptides of M. japonicus and L. vannamei showed a similar inhibitory activity using the same bioassay system [15][16][17]. However, meaningful inhibitory activity was observed also in a type II peptide (Mej-SGP-II) in the present study.…”

“…Open boxes indicate the positions of conserved Cys residues. Gray box represents characteristic of type II peptides, which is an insertion of a Gly residue at position 12 having vitellogenesis-inhibiting and hyperglycemic activities [8,16], was important for the folding of the molecule to its natural conformation and significant for conferring hyperglycemic activity [23]. These results suggest that Mej-SGP-II might have a C-terminal amide.…”

“…In the kuruma prawn Marsupenaeus japonicus, eight CHH-family peptides, which were designated as Pej-SGP (sinus gland peptide)-I to -VII and Pej-MIH-B, have been purified from the sinus glands [7,8,[12][13][14]. Two type II peptides, Pej-SGP-IV and Pej-MIH-B, exhibited moltinhibiting activity but no significant effect on vitellogenin (vg) gene expression [7,[14][15][16], while the other six type I peptides (Pej-SGP-I, II, III, V, VI, and VII) displayed vitellogenesis-inhibiting activity (in terms of the inhibition of vg expression) on the ovary as well as hyperglycemic activity [8,13,15,16]. In the whiteleg shrimp Litopenaeus vannamei, six type I peptides (Liv-SGP-A, -B, -C, -E, -F, and -G) represented similar vitellogenesis-inhibiting activity, but a type II peptide Liv-SGP-D did not [17].…”

Transcriptomic Analysis of the Kuruma Prawn Marsupenaeus japonicus Reveals Possible Peripheral Regulation of the Ovary

“…The reproductive processes of M. japonicus have also been extensively studied using vitellogenesis-related proteins and their genes (e.g., VG, cathepsin C, cortical rod protein, and thrombospondin) as indices of ovarian development (15)(16)(17)(18)(19)(20)(21). Among various peptide hormones which have been purified and characterized from the central XOSG (22)(23)(24)(25)(26)(27), six type-I peptides of the crustacean hyperglycemic hormone (CHH) superfamily inhibit the expression of VG in the ovary (28,29). Consequently, the six CHHs, called as P. japonicus sinus gland peptide-I (Pej-SGP-I), -II -III, -V, -VI, and -VII, have been hypothesized to be vitellogenesis-inhibiting hormones (VIHs), which explains why eyestalk-ablation acceralates ovarian development.…”

Differential regulation of hepatopancreatic vitellogenin (VTG) gene expression by two putative molt-inhibiting hormones (MIH1/2) in Pacific white shrimp (Litopenaeus vannamei)

“…The process of vitellogenesis in crustaceans is widely assumed to be negatively controlled by VIH [4,23,26]. However, recent studies revealed that other members of CHH family may also play a role in regulating vitellogenesis [5,12,25,29]. MIH is one of the potential reproductive regulators of CHH family.…”