caa a22 4500 445821191 CHVBK 20180317145244.0 cr unu---uuuuu 170323e20110301xx s 000 0 eng 10.1007/s00239-011-9432-9 doi (NATIONALLICENCE)springer-10.1007/s00239-011-9432-9 Polymorphisms in the Extracellular Region of Dopamine Receptor D4 Within and Among Avian Orders [Elektronische Daten] [Hideaki Abe, Shin'ichi Ito, Miho Inoue-Murayama] Polymorphisms in the dopamine receptor D4 gene (DRD4) have been widely investigated to assess their correlation with variations in animal behavior. We precisely examined polymorphisms in the extracellular region of DRD4 in 75 avian species belonging to 16 orders and detected high degrees of polymorphism at inter- and intraordinal levels. The existence of a variable number of proline repeats (2 to 12 times) in the extracellular region was a common feature in all Neognathae, and a strong codon bias at synonymous sites was found among Passeriformes, Galliformes, and other non-passerine Neoaves. Furthermore, significantly higher values of the pairwise disparity index were detected in Passeriformes, suggesting either a substantial difference in the evolutionary processes or a higher level of mutation rate in the passerine clade. The differences in both codon bias and other genetic parameters among avian taxa would be explained by different levels of selective pressure on the extracellular region of DRD4. Our study suggested that different conformations determined in a sequence-dependent manner at the extracellular region could be one of the key factors affecting the efficiency and accuracy of DRD4 expression. Our findings further imply a possibility that behavioral diversity, which would be important during the processes of adaptive radiation, may be enhanced by the selection acting on indels or single-nucleotide substitutions in the extracellular region of DRD4. Springer Science+Business Media, LLC, 2011 Dopamine receptor D4 ( DRD4 ) nationallicence Polymorphism nationallicence Codon bias nationallicence Extracellular region nationallicence Avian nationallicence Neoaves nationallicence Proline repeats nationallicence Selective pressure nationallicence Abe Hideaki Wildlife Research Center of Kyoto University, 2-24 Tanaka-Sekiden-cho, Sakyo-ku, 606-8203, Kyoto, Japan aut Ito Shin'ichi Faculty of Applied Biological Sciences, Gifu University, 501-1193, Gifu, Japan aut Inoue-Murayama Miho Wildlife Research Center of Kyoto University, 2-24 Tanaka-Sekiden-cho, Sakyo-ku, 606-8203, Kyoto, Japan aut Journal of Molecular Evolution Springer-Verlag 72/3(2011-03-01), 253-264 0022-2844 72:3<253 2011 72 239 https://doi.org/10.1007/s00239-011-9432-9 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00239-011-9432-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Abe Hideaki Wildlife Research Center of Kyoto University, 2-24 Tanaka-Sekiden-cho, Sakyo-ku, 606-8203, Kyoto, Japan aut NATIONALLICENCE 700 1- Ito Shin'ichi Faculty of Applied Biological Sciences, Gifu University, 501-1193, Gifu, Japan aut NATIONALLICENCE 700 1- Inoue-Murayama Miho Wildlife Research Center of Kyoto University, 2-24 Tanaka-Sekiden-cho, Sakyo-ku, 606-8203, Kyoto, Japan aut NATIONALLICENCE 773 0- Journal of Molecular Evolution Springer-Verlag 72/3(2011-03-01), 253-264 0022-2844 72:3<253 2011 72 239 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer