title: Annotation of the Daphnia magna nuclear receptors: comparison to Daphnia pulex.
abstract: Most nuclear receptors (NRs) are ligand-dependent transcription factors crucial in homeostatic physiological responses or environmental responses. We annotated the Daphnia magna NRs and compared them to Daphnia pulex and other species, primarily through phylogenetic analysis. Daphnia species contain 26 NRs spanning all seven gene subfamilies. Thirteen of the 26 receptors found in Daphnia species phylogenetically segregate into the NR1 subfamily, primarily involved in energy metabolism and resource allocation. Some of the Daphnia NRs, such as RXR, HR96, and E75 show strong conservation between D. magna and D. pulex. Other receptors, such as EcRb, THRL-11 and RARL-10 have diverged considerably and therefore may show different functions in the two species. Curiously, there is an inverse association between the number of NR splice variants and conservation of the LBD. Overall, D. pulex and D. magna possess the same NRs; however not all of the NRs demonstrate high conservation indicating the potential for a divergence of function.
authors.affiliation: Biological Sciences, Clemson University, United States.
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Litoff
authors.affiliation: Biological Sciences, Clemson University, United States.
authors.forename: Travis E
authors.initials: TE
authors.lastname: Garriott
authors.affiliation: Environmental Toxicology Program, Clemson University, United States.
authors.forename: Gautam K
authors.initials: GK
authors.lastname: Ginjupalli
authors.affiliation: Biological Sciences, Clemson University, United States.
authors.forename: LaToya
authors.initials: L
authors.lastname: Butler
authors.affiliation: Biological Sciences, Clemson University, United States.
authors.forename: Claudy
authors.initials: C
authors.lastname: Gay
authors.affiliation: Biological Sciences, Clemson University, United States.
authors.forename: Kiandra
authors.initials: K
authors.lastname: Scott
authors.affiliation: Biological Sciences, Clemson University, United States; Environmental Toxicology Program, Clemson University, United States. Electronic address: Baldwin@clemson.edu.
authors.forename: William S
authors.initials: WS
authors.lastname: Baldwin
mesh_terms: D000818:Animals; D003621:Daphnia / Q000235:genetics*; D010802:Phylogeny; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics*
chemical_list: D018160:Receptors, Cytoplasmic and Nuclear
keywords: Arthropod; Crustacea; Evolution; Phylogenetics