Molecular cloning, expression analysis and functional confirmation of two ecdysone receptor isoforms from the rice stem borer Chilo suppressalis.
PCR techniques were used to clone and identify cDNAs for ecdysone receptor A and B1 (EcR-A and EcR-B1) isoforms from the rice stem borer, Chilo suppressalis. They differ only in the N-terminal A/B regions and show high sequence identities to other insects' EcRs. At the wandering stage, EcR-B1 mRNA was expressed more abundantly in the midgut than in the epidermis and fat body, whereas expression levels of EcR-A mRNA were similar in the three tissues. In the epidermis of the last instar larvae, the maximal mRNA expression of both EcR-A and EcR-B1 was observed from the wandering to prepupal stages prior to the peak of ecdysteroid titer in the hemolymph. In gel mobility shift assays, in vitro translated C. suppressalis EcR-B1 (CsEcR-B1) and Bombyx mori ultraspiracle (BmUSP) proteins bound to the Pal 1 and Drosophila melanogaster hsp27 ecdysone response element as a heterodimer. These results indicate that the cDNAs isolated here encode functional ecdysone receptors.
Minakuchi
C
C
Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
Nakagawa
Y
Y
Kiuchi
M
M
Tomita
S
S
Kamimura
M
M
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary; D026461:Ecdysteroids / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D015870:Gene Expression; D006458:Hemolymph / Q000378:metabolism; D019476:Insect Proteins; D008969:Molecular Sequence Data; D009036:Moths / Q000235:genetics* / Q000378:metabolism; D020033:Protein Isoforms / Q000235:genetics; D012333:RNA, Messenger; D011987:Receptors, Steroid / Q000235:genetics*; D017386:Sequence Homology, Amino Acid
D018076:DNA, Complementary; D026461:Ecdysteroids; D019476:Insect Proteins; D020033:Protein Isoforms; D012333:RNA, Messenger; D011987:Receptors, Steroid; C055469:ecdysone receptor; C467903:ecdysone receptor A, insect