title: Why does the giant panda eat bamboo? A comparative analysis of appetite-reward-related genes among mammals.
abstract: BACKGROUND
  The giant panda has an interesting bamboo diet unlike the other species in the order of Carnivora. The umami taste receptor gene T1R1 has been identified as a pseudogene during its genome sequencing project and confirmed using a different giant panda sample. The estimated mutation time for this gene is about 4.2 Myr. Such mutation coincided with the giant panda's dietary change and also reinforced its herbivorous life style. However, as this gene is preserved in herbivores such as cow and horse, we need to look for other reasons behind the giant panda's diet switch.
  
  
  RESULTS
  Since taste is part of the reward properties of food related to its energy and nutrition contents, we did a systematic analysis on those genes involved in the appetite-reward system for the giant panda. We extracted the giant panda sequence information for those genes and compared with the human sequence first and then with seven other species including chimpanzee, mouse, rat, dog, cat, horse, and cow. Orthologs in panda were further analyzed based on the coding region, Kozak consensus sequence, and potential microRNA binding of those genes.
  
  
  CONCLUSIONS
  Our results revealed an interesting dopamine metabolic involvement in the panda's food choice. This finding suggests a new direction for molecular evolution studies behind the panda's dietary switch.
authors.affiliation: School of Life Sciences, Fudan University, Shanghai, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Jin
authors.forename: Chenyi
authors.initials: C
authors.lastname: Xue
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Wu
authors.forename: Jinyi
authors.initials: J
authors.lastname: Qian
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhu
authors.forename: Zhen
authors.initials: Z
authors.lastname: Yang
authors.forename: Takahiro
authors.initials: T
authors.lastname: Yonezawa
authors.forename: M James C
authors.initials: MJ
authors.lastname: Crabbe
authors.forename: Ying
authors.initials: Y
authors.lastname: Cao
authors.forename: Masami
authors.initials: M
authors.lastname: Hasegawa
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhong
authors.forename: Yufang
authors.initials: Y
authors.lastname: Zheng
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D001066:Appetite / Q000235:genetics*; D031723:Bambusa; D001483:Base Sequence; D002394:Catechol O-Methyltransferase / Q000737:chemistry / Q000235:genetics; D003198:Computer Simulation; D016384:Consensus Sequence / Q000235:genetics; D060434:Herbivory / Q000235:genetics*; D006801:Humans; D008322:Mammals / Q000235:genetics*; D035683:MicroRNAs / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D059372:Nucleotide Motifs / Q000235:genetics; D016366:Open Reading Frames / Q000235:genetics; D012201:Reward; D016415:Sequence Alignment; D001503:Ursidae / Q000235:genetics*
chemical_list: D020413:3' Untranslated Regions; D035683:MicroRNAs; D002394:Catechol O-Methyltransferase