Isolation and cDNA cloning of cholecystokinin from the skin of Rana nigrovittata.
Many neuroendocrine peptides that are distributed in amphibian gastrointestinal tract and central nervous system are also found in amphibian skins, and these peptides are classified into skin-gut-brain triangle peptides, such as bombesins, gastrin-releasing peptides. Cholecystokinins (CCKs) are neuroendocrine peptides known for their production in the gastrointestinal tract and central nervous system of mammalians. Several CCKs have been identified from two amphibians, Rana catesbeiana and Xenopus laevis. These amphibian CCKs are found to be express in brain and in the gastrointestinal tract, but not in skin. In the current report, a cholecystokinin (CCK) isoform was identified from skin secretions of the frog, Rana nigrovittata. Its amino acid sequence is RVDGNSDQKAVIGAMLAKDLQTRKAGSSTGRYAVLPNR PVIDPTHRINDRDYMGWMDF, which is the same with that of CCK from R. catesbeiana. Four different cDNAs (GenBank accession nos. EF608063-6) encoding CCK precursors were cloned from the cDNA library of the skin of R. nigrovittata. The present data demonstrated that amphibian CCK could also be expressed in gastrointestinal tract, central nervous system and skin as other amphibian skin-gut-brain triangle peptides.
Liu
Xiuhong
X
Key Laboratory of Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, Life Sciences College of Nanjing Agricultural University, Nanjing, Jiangsu 210095, China.
Wang
Yipeng
Y
Cheng
Lihua
L
Song
Yuzhu
Y
Lai
Ren
R
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002766:Cholecystokinin / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D008969:Molecular Sequence Data; D011892:Rana catesbeiana / Q000235:genetics; D011898:Ranidae / Q000235:genetics* / Q000502:physiology*; D017386:Sequence Homology, Amino Acid; D012867:Skin / Q000378:metabolism; D013045:Species Specificity; D014982:Xenopus laevis / Q000235:genetics
D018076:DNA, Complementary; D002766:Cholecystokinin