Three cDNAs encoding vitellogenin homologs from Antarctic copepod, Tigriopus kingsejongensis: Cloning and transcriptional analysis in different maturation stages, temperatures, and putative reproductive hormones.

Three full-length cDNAs encoding lipoprotein homologs were identified in Tigriopus kingsejongensis, a newly identified copepod from Antarctica. Structural and transcriptional analyses revealed homology with two vitellogenin-like proteins, Tik-Vg1 and Tik-Vg2, which were 1855 and 1795 amino acids in length, respectively, along with a third protein, Tik-MEP, which produced a 1517-residue protein with similarity to a melanin engaging protein (MEP) in insects Phylogenetic analysis showed that Vgs in Maxillopods including two Tik-Vgs belong to the arthropod vitellogenin-like clade, which includes clottable proteins (CPs) in decapod crustaceans and vitellogenins in insects. Tik-MEP clustered together with insect MEPs, which appear to have evolved before the apoB-like and arthropod Vg-like clades. Interestingly, no genes orthologous to those found in the apoB clade were identified in Maxillopoda, suggesting that functions of large lipid transfer proteins (LLTPs) in reproduction and lipid metabolism may be different from those in insect and decapod crustaceans. As suggested by phylogenetic analyses, the two Tik-Vgs belonging to the arthropod Vg-like clade appear to play major roles in oocyte maturation, while Vgs belonging to the apoB clade function primarily in the reproduction of decapod crustaceans. Transcriptional analysis of Tik-Vg expression revealed a 24-fold increase in mature and ovigerous females compared with immature female, whereas expression of Tik-MEP remained low through all reproductive stages. Acute temperature changes did not affect the transcription of Tik-Vg genes, whereas Tik-MEP appeared to be affected by temperature change. Among the three hormones thought to be involved in molting and reproduction in arthropods, only farnesoic acid (FA) induced transcription of the two Tik-Vg genes. Regardless of developmental stage and hormone treatment, Tik-Vg1 and Tik-Vg2 exhibited a strong positive correlation in expression, suggesting that expression of these genes may be regulated by the same transcriptional machinery.

Lee SR ，Lee JH ，Kim AR ，Kim S ，Park H ，Baek HJ ，Kim HW ... -  《-》

Molecular characterization and expression of vitellogenin (Vg) genes from the cyclopoid copepod, Paracyclopina nana exposed to heavy metals.

Hwang DS ，Lee KW ，Han J ，Park HG ，Lee J ，Lee YM ，Lee JS ... -  《COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-TOXICOLOGY & PHARMACOLOGY》

Molecular cloning, phylogenetic analysis and developmental expression of a vitellogenin (Vg) gene from the intertidal copepod Tigriopus japonicus.

Lee KW ，Hwang DS ，Rhee JS ，Ki JS ，Park HG ，Ryu JC ，Raisuddin S ，Lee JS ... -  《COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY》

Characterization of two vitellogenin cDNAs from a Pandalus shrimp (Pandalopsis japonica): expression in hepatopancreas is down-regulated by endosulfan exposure.

Endosulfan is a neurotoxic organochlorine insecticide of the cyclodiene family of pesticides that inhibits molting and reproduction in aquatic crustaceans. In order to determine the molecular mechanism of endosulfan as an endocrine disrupting chemical (EDC), differential display RT-PCR (DDRT-PCR) was used to isolate genes in the shrimp, Pandalopsis japonica, affected by endosulfan exposure. PCR screening of cDNA from the hepatopancreas from control and endosulfan-exposed animals, using 120 sets of random primers, yielded partial cDNAs encoding two vitellogenin-like proteins (Pj-Vg1 and -Vg2). Complete sequences were obtained using a combination of RT-PCR and RACE-PCR. Pj-Vg1 (7883bp) encoded a protein composed of 2533 amino acid residues (283.27 kDa estimated mass), whereas Pj-Vg2 (7792 bp) encoded a protein composed of 2537 amino acids residues (284.87 kDa estimated mass). Alignment of the Pj-Vgs with those of other vitellogenins identified a conserved subtilisin cleavage site (RQKR) and the lipoprotein N-terminal (vitellin), DUF1081, and von Willebrand factor type D domains, indicating both genes encoded functional proteins. Phylogenetic analysis showed that Pj-Vg1 and -Vg2 were most similar to Pandalus hypsinotus Vg. Both Pj-Vg1 and -Vg2 were expressed primarily in the hepatopancreas, although the Pj-Vg2 transcript was also detected in the ovary. The effects of the 3-day endosulfan exposure (2.5 microg/L and 25 microg/L) on Vg expression in the hepatopancreas were determined by quantitative RT-PCR. Expression of both transcripts was significantly inhibited at 25 microg/L suggesting that Pj-Vgs can be used as indicator for endosulfan exposure.

Jeon JM ，Lee SO ，Kim KS ，Baek HJ ，Kim S ，Kim IK ，Mykles DL ，Kim HW ... -  《-》

Evidence for two vitellogenin-related genes in Leucophaea maderae: the protein primary structure and its processing.

Tufail M ，Bembenek J ，Elgendy AM ，Takeda M ... -  《ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY》