~ 2083 ~ International Journal of Chemical Studies 2018; 6(5): 2083-2091 P-ISSN: 2349–8528 E-ISSN: 2321–4902 IJCS 2018; 6(5): 2083-2091 © 2018 IJCS Received: 25-07-2018 Accepted: 30-08-2018 Gagan Rani Department of Chemistry, Chaudhary Charan Singh Haryana Agricultural University, Hisar, Haryana, India Neha Gupta Department of chemistry, Biotechnology and Bioinformatics, Chaudhary Charan Singh Haryana Agricultural University, Hisar Haryana, India, Neeru Singh Redhu Department of Molecular Biology, Biotechnology and Bioinformatics, Chaudhary Charan Singh Haryana Agricultural University, Hisar, Haryana, India Sudhir Kumar Department of Molecular Biology, Biotechnology and Bioinformatics, Chaudhary Charan Singh Haryana Agricultural University, Hisar, Haryana, India Correspondence Gagan Rani Department of Chemistry, Chaudhary Charan Singh Haryana Agricultural University, Hisar, Haryana, India Phylogenetic and comparative analysis of Drosophila melanogaster ecdysone receptor Gagan Rani, Neha Gupta, Neeru Singh Redhu and Sudhir Kumar Abstract Ecdysone receptor (EcR), a heterodimer of the EcR and Ultraspiracle (USP) nuclear receptors; helps in regulation, reproduction, larval molting, and metamorphosis. In insects, EcR is activated by ecdysteroids. USP nuclear hormone receptor of the insects orthologs to mammalian Retinoid X receptor (RXR) protein. Ecdysone receptor is target for a wide range of pesticides and insecticides. These insecticides binds to their respective target sites in turn hinder the activity of ecdysone and retard the growth of insects. The study was focused on phylogenetic and comparative study of Drosophila ecdysone receptor with its orthologs. Physiochemical properties such as molecular weight, theoretical isoelectric point, extinction coefficient, aliphatic index, instability index, total number of negatively and positively charged residues and grand average of hydropathicity were computed. Along with these physiochemical properties cellular localilization, no. of transmembrane helices, other proteins with which this protein interact and gene ontology were also depicted using various tools. Keywords: Ecdysone receptor, nuclear receptor, comparative study Introduction Insect development, namely metamorphosis, is regulated by the steroid hormone ecdysone (Thummel, 1995, 1996) [10, 11] and its counteragent juvenile hormone. Ecdysone receptor was a type of nuclear receptors (NRs), are a well-characterized superfamily of proteins containing over 150 members. The nuclear receptors are modular proteins, containing conserved domains for DNA-binding, ligand-binding (LDB) and other functions (Gronemeyer & Laudet, 1995). The physiological process of molting in insects is governed by hormones. The ecdysteroid hormones coordinate the major stages of insect development by binding to the ecdysone receptor (EcR). Ecdysone acts through the ecdysone receptor, a heterodimer of the EcR and USP nuclear receptors, to regulate reproduction, larval molting, and metamorphosis in insects, binds to and is activated by ecdysteroids. Ecdysteroids are the steroid hormones of arthropods, where they regulate moulting, metamorphosis, reproduction and diapause (Koolman 1989). These nuclear hormone receptor proteins are the insect orthologs of the mammalian retinoid X receptor (RXR) protein. The RXR is a type of nuclear receptor that is activated by 9-cis retinoic acid. The ecdysone receptor ECR, a nuclear transcription factor controlling insect development, is a novel target for Insecticides. Nuclear receptors (NRs) are a well- characterized superfamily of proteins containing over 150 members. The nuclear receptors are modular proteins, containing conserved domains for DNA-binding, ligand-binding (LDB) and other functions. Ecdysone acts in the form of its active metabolite 20–hydroxyecdysone (20E) by binding to the ecdysone receptor (ECR). RXR is capable of binding and being activated by different types of ligands, such as the potent retinoid 9-cis retinoic acid (9cRA) (Heyman et al., 1992; Levin et al., 1992) [5, 8] , unsaturated fatty acids (de Urquiza et al., 2000; Kitareewan et al., 1996) [3, 7] and various synthetic ligands (Szanto et al., 2004) [12] . The DNA binding Usp, mediates its function. A peak of ecdysone in late 3rd instar larvae (Ashburner, 1972) [1] activates transcription of ‘early’ genes in salivary glands (Huet et al., 1995) [6] , including Broad Complex (BR-C) and two homologs of mammalian Rev-Erb, E75A and E75B, which in turn activate a set of ‘late’ genes. When the level of ecdysone diminishes at the prepupal stage, the unliganded EcR/Usp complex is thought to directly repress these and other ecdysone- inducible genes. While the role of EcR/ Usp in ecdysone-dependent activation is well established, its ability to repress genes in the absence of ecdysone is less so. EcR/Usp, like mammalian NRs, recruits co-regulators. Once recruited, co-regulators modify histones, resulting in altered chromatin