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This article contains structure and pharmacological characteristics of melanocortin receptors (MCRs) related to research published in “Characterization of melanocortin receptors from stingray Dasyatis akajei, a cartilaginous fish” (Takahashi et al., 2016) . The amino acid sequences of the stingray, D. akajei, MC1R, MC2R, MC3R, MC4R, and MC5R were aligned with the corresponding melanocortin receptor sequences from the elephant shark, Callorhinchus milii, the dogfish, Squalus acanthias, the goldfish, Carassius auratus, and the mouse, Mus musculus. These alignments provide the basis for phylogenetic analysis of these gnathostome melanocortin receptor sequences. In addition, the Japanese stingray melanocortin receptors were separately expressed in Chinese Hamster Ovary cells, and stimulated with stingray ACTH, α-MSH, β-MSH, γ-MSH, δ-MSH, and β-endorphin. The dose response curves reveal the order of ligand selectivity for each stingray MCR.
Value of the data
Data provided in this article show amino acid sequence comparison of melanocortin receptors (MCRs) in vertebrates and ligand selectivity of stingray MC peptides on these receptors. The amino acids sequences of MC1R (Fig. 1), MC2R (Fig. 2), MC3R (Fig. 3), MC4R (Fig. 4), and MC5R (Fig. 5) of stingray (Squalus acanthias) which determined by us  were compared to corresponding sequences from two species of other cartilaginous fishes (i.e., Callorhinchus milii, elephant shark and S. acanthias, dogfish), a teleost (Carassius auratus, goldfish), and a mammal (Mus musculus, mouse). Data are also provided for ligand selectivity include effects of stingray Des-acetyl-α-MSH, β-MSH, γ-MSH, δ-MSH, ACTH(1-24) and β-endorphin on MC1R, MC3R, MC4R, and MC5R (Fig. 6, Fig. 8, Fig. 9, Fig. 10) and those of stingray Des-acetyl-α-MSH, ACTH(1-24), human ACTH(1-24) and NDP-MSH on stingray MC2R (Fig. 7).
In order to align the amino acid sequences of the melanocortin receptors for the Japanese stingray, D. akajei, the dogfish, S. acanthias, the elephant shark, C. milii, the goldfish, C. auratus, and the mouse, M. musculus, it was essential to identify putative transmembrane domains in each receptor sequence. To this end, the program ‘‘MEMSAT3’’ (http://bioinf.cs.ucl.ac.uk/psipred/) was used. The amino acid sequences where then aligned using the program MEGA 6.0.
To functionally express and determine the ligand selectivity of the stingray (sr) MC1R, srMC2R, srMC3R, srMC4R, and srMC5R paralogs, the nucleotide sequences for the srmcrs were separately synthesized with a V-5 epitope tag at the N-terminal of the receptor, and inserted into a pcDNA3.1 expression vector (GenScript; Picataway, NJ, USA). Each srmcr cDNA was separately transiently transfected into Chinese Hamster Ovary (CHO) cells. The CHO cells were grown at 37 °C in a humidified 5% CO2 incubator in DMEM/F12 with 5% fetal calf serum. Each sr cDNA was co-expressed with a CRE/Luciferase reporter plasmid  using the Solution T Cell Line Nucleofector Kit (Amaxa Inc., Gaithersburg, MD, USA) and program U-23 . The transiently transfected cells were seeded on a 96-well plate at a density of 1×10−5 cells/well. After 48 h in culture, the transfected cells were stimulated with either synthetic srACTH(1-24), srDes-acetyl-α-MSH, srβ-MSH, srγ-MSH, srδ-MSH, srβ-endorphin or hACTH(1-24), or NDP-MSH at concentrations ranging from 10−6 M to 10−12 M, in serum-free CHO media for four hours at 37 °C. At the end of the incubation period, 100 µl of Bright-Glo luciferase assay reagent (Promega Inc., Madison, WI, USA) was added to each well, and incubated for 5 min at room temperature. Luminescence was measured with a Bio-Tek Synergy HT plate reader (Bio Tek, Winooski, VT, USA), and the dose response curves were analyzed by using Kaleidagraph software (Synergy Software, Reading, PA, USA). All experimental treatments were performed in triplicate.
We thank Mr. Kosuke Arai, Kitasato University, and Dr. Yasuhisa Kobayashi, Dr. Naoaki Tsutsui and Mr. Kazuhiro Saito, Okayama University, for technical assistance. Partial support for this study was provided by the Long Research Fund (RMD) and National Science Foundation, U.S.A. Grant IOB 0516958 Supplement (RMD).
Appendix ASupplementary data associated with this article can be found in the online version at doi:10.1016/j.dib.2016.04.050.