Jiang Yanyun, Lin Xinda
College of Life Sciences, China Jiliang University, Hangzhou 310018, China.
College of Life Sciences, China Jiliang University, Hangzhou 310018, China.
Comp Biochem Physiol B Biochem Mol Biol. 2018 Jul;221-222:1-10. doi: 10.1016/j.cbpb.2018.04.003. Epub 2018 Apr 11.
The brown planthopper ATP-binding cassette (ABC) proteins White (W), Scarlet (St) and Brown (Bw) belong to the ABC transporter superfamily and are responsible for the transportation of guanine and tryptophan precursors of eye pigments. In the present study, the brown planthopper White (NlW), S t(NlSt) and Bw (NlBw) genes were cloned, and subsequent phylogenetic analysis showed that these genes are clustered with their respective homologues, with a genetic relationship observed between NlW and its Bemisia tabaci homologue having the highest similarity. Sequence alignments showed that these three proteins have a highly conserved Walker A domain, an ABC "signature sequence" and a Walker B domain. QRT-PCR demonstrated that W, St and Bw are highly expressed in the head of long-winged males and are highly expressed in both egg and male. Adult eye colour was altered after the downregulation of NlW, NlSt and NlBw in the 1st to 3rd instar nymph. The eye colours of emerged adults became white, dark and red after injection of dsNlW, dsNlSt and dsNlBw, respectively. The eye pigment content assay revealed that xanthommatin and pteridine were significantly decreased after the injection of dsRNAs, and the range of variation was inversely correlated with nymph age. The present study provides a theoretical basis for understanding the function of ABC transporters at the molecular and biochemical levels.
褐飞虱ATP结合盒(ABC)蛋白白色(W)、猩红色(St)和棕色(Bw)属于ABC转运蛋白超家族,负责眼色素鸟嘌呤和色氨酸前体的运输。在本研究中,克隆了褐飞虱白色(NlW)、St(NlSt)和Bw(NlBw)基因,随后的系统发育分析表明,这些基因与其各自的同源物聚类,观察到NlW与其相似度最高的烟粉虱同源物之间存在遗传关系。序列比对表明,这三种蛋白具有高度保守的沃克A结构域、ABC“特征序列”和沃克B结构域。定量逆转录聚合酶链反应(QRT-PCR)表明,W、St和Bw在长翅雄虫头部高度表达,在卵和雄虫中均高度表达。在1至3龄若虫中下调NlW、NlSt和NlBw后,成虫眼颜色发生改变。注射dsNlW、dsNlSt和dsNlBw后,羽化成虫的眼颜色分别变为白色、深色和红色。眼色素含量测定表明,注射dsRNA后,黄蝶呤和蝶啶显著降低,变化范围与若虫年龄呈负相关。本研究为在分子和生化水平上理解ABC转运蛋白的功能提供了理论依据。