Rao V Venkat, Ningshen Thuirei Jacob, Chaitanya R K, Senthilkumaran B, Dutta-Gupta Aparna
Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
Department of Biotechnology, Manipur University, Canchipur, Manipur 795003, India.
Comp Biochem Physiol B Biochem Mol Biol. 2016 Apr-May;194-195:58-64. doi: 10.1016/j.cbpb.2016.01.008. Epub 2016 Jan 27.
In the present study, a riboflavin-binding hexamerin (RbHex) was cloned and characterized from the larval fat body of Corcyra cephalonica. The complete cDNA (2121bp) encodes a 706-amino acid protein with a molecular mass ~82kDa. Expression of RbHex 82 was predominant in fat body among larval tissues. Further, it is prominently expressed during the last instar larval development. Homology modeling and docking studies predicted riboflavin binding site of the hexamerin. Spectrofluorimetric analysis further confirmed riboflavin release from the hexamerin fraction. Quantitative RT-PCR studies demonstrated hormonal regulation of RbHex 82. 20-Hydroxyecdysone (20HE) had a stimulatory effect on its transcription whereas JH alone did not show any effect. However, JH in the presence of 20HE maintains the RbHex 82 expression which indicates the JH's role as a status quo factor. This study is the first to report the characterization of riboflavin-binding hexamerin in a lepidopteran pest. Further, the possibility of RbHex 82 as a pest control target is discussed.
在本研究中，从印度谷螟幼虫脂肪体中克隆并鉴定了一种核黄素结合六聚体蛋白（RbHex）。完整的cDNA（2121bp）编码一个706个氨基酸的蛋白质，分子量约为82kDa。RbHex 82在幼虫组织中的脂肪体中表达占主导。此外，它在末龄幼虫发育期间显著表达。同源建模和对接研究预测了六聚体蛋白的核黄素结合位点。荧光光谱分析进一步证实了核黄素从六聚体组分中的释放。定量RT-PCR研究证明了RbHex 82的激素调节作用。20-羟基蜕皮酮（20HE）对其转录有刺激作用，而单独的保幼激素（JH）没有任何作用。然而，在20HE存在的情况下，JH维持RbHex 82的表达，这表明JH作为一种维持现状因子的作用。本研究首次报道了鳞翅目害虫中核黄素结合六聚体蛋白的特性。此外，还讨论了RbHex 82作为害虫防治靶标的可能性。
