title: Motilin and ghrelin gene experienced episodic evolution during primitive placental mammal evolution.
abstract: Motilin and ghrelin, members of a structure-function-related hormone family, play important roles in gastrointestinal function, regulation of energy homeostasis and growth hormone secretion. We observed episodic evolution in both of their prehormone gene sequences during primitive placental mammal evolution, during which most of the nonsynonymous changes result in radical substitution. Of note, a functional obestatin hormone might have only originated after this episodic evolution event. Early in placental mammal evolution, a series of biology complexities evolved. At the same time the motilin and ghrelin prehormone genes, which play important roles in several of these processes, experienced episodic evolution with dramatic changes in their coding sequences. These observations suggest that some of the lineage-specific physiological adaptations are due to episodic evolution of the motilin and ghrelin genes.
authors.affiliation: State Key Laboratory of Genetic Resource and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, China.
authors.forename: Jing
authors.initials: J
authors.lastname: He
authors.forename: M David
authors.initials: MD
authors.lastname: Irwin
authors.forename: YaPing
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005075:Biological Evolution; D005260:Female; D054439:Ghrelin / Q000737:chemistry / Q000235:genetics*; D008322:Mammals / Q000145:classification / Q000235:genetics*; D008969:Molecular Sequence Data; D009037:Motilin / Q000737:chemistry / Q000235:genetics*; D010802:Phylogeny; D010920:Placenta; D011247:Pregnancy; D017386:Sequence Homology, Amino Acid
chemical_list: D054439:Ghrelin; D009037:Motilin