Expression and localization of aquaporin-1 on the apical membrane of enterocytes in the small intestine of bottlenose dolphins.
The small and large intestines are primary sites for water intake in mammals. To reveal how water is absorbed in the intestines of cetaceans, histological and molecular-biological studies were performed on the small intestine of the bottlenose dolphin, Tursiops truncatus. In histological studies using fresh specimens, obvious villi and deep crypts of Lieberkühn, lined by abundant enterocytes with microvilli and goblet cells, were observed in the mucosa. Expressions and immunolocalizations of aquaporin-1 (AQP1), a member of the water-selective channel termed AQP, were also investigated in the intestine. By reverse transcriptional polymerase chain reaction and rapid amplification of cDNA ends using RNA extracted from the dolphins' small intestines, the full length of mRNA for AQP1 was sequenced. The deductive amino acid sequence for an open reading frame showed high homologies with other mammals' AQP1, and water permeability of the protein was certified by cRNA injection to Xenopus oocytes. Immunohistochemistry showed AQP1 distribution on the apical membrane of the enterocytes, especially in the crypts. These data suggest that AQP1 is a channel protein responsible for water absorption in the small intestine of dolphins.
Suzuki
Miwa
M
Department of Marine Science and Resources, College of Bioresource Sciences, Nihon University, Fujisawa, Kanagawa, 252-8510, Japan. suzuki.miwa@nihon-u.ac.jp
D000042:Absorption / Q000502:physiology; D000595:Amino Acid Sequence; D000818:Animals; D051398:Aquaporin 1 / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D050681:Bottle-Nosed Dolphin / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism*; D018076:DNA, Complementary / Q000378:metabolism; D020895:Enterocytes / Q000378:metabolism* / Q000648:ultrastructure; D007421:Intestine, Small / Q000378:metabolism*; D008297:Male; D008969:Molecular Sequence Data; D010802:Phylogeny; D012333:RNA, Messenger / Q000378:metabolism; D014867:Water / Q000378:metabolism
D018076:DNA, Complementary; D012333:RNA, Messenger; D014867:Water; D051398:Aquaporin 1
Eur J Cell Biol. 2001 Nov;80(11):711-9
11824790
J Histochem Cytochem. 1999 Oct;47(10):1275-86
10490456
J Mol Biol. 2005 Jul 8;350(2):278-89
15922355
Am J Physiol Renal Physiol. 2001 Dec;281(6):F1047-57
11704555
J Biol Chem. 1991 Apr 5;266(10):6407-15
2007592
J Exp Biol. 2003 Oct;206(Pt 19):3495-505
12939380
Nucleic Acids Res. 1994 Nov 11;22(22):4673-80
7984417
J Am Vet Med Assoc. 1970 Sep 1;157(5):555-8
5452073
Biochem Cell Biol. 2007 Dec;85(6):675-84
18059526
Science. 1992 Apr 17;256(5055):385-7
1373524
Biochem Biophys Res Commun. 2001 Oct 5;287(4):814-9
11573934
Am J Physiol Cell Physiol. 2005 May;288(5):C1161-70
15647389
Am J Physiol Regul Integr Comp Physiol. 2005 Jun;288(6):R1733-43
15650119
Biochim Biophys Acta. 2002 Jan 30;1542(1-3):116-24
11853885
J Physiol. 1999 Jun 1;517 ( Pt 2):317-26
10332084
Curr Opin Cell Biol. 1994 Dec;6(6):795-803
7880525
Am J Physiol Regul Integr Comp Physiol. 2002 Sep;283(3):R779-88
12185013
World J Gastroenterol. 2006 Feb 21;12(7):1092-7
16534851
FEBS Lett. 2003 Nov 27;555(1):72-8
14630322
Int J Tissue React. 2005;27(2):51-8
16035648
J Physiol. 2002 Jul 1;542(Pt 1):53-60
12096049
Prog Histochem Cytochem. 2004;39(1):1-83
15242101
Biol Cell. 2005 Nov;97(11):823-9
15898950
Biol Cell. 2005 Aug;97(8):605-13
15943587
Physiol Rev. 2002 Jan;82(1):205-44
11773613
Proc Natl Acad Sci U S A. 1991 Dec 15;88(24):11110-4
1722319
J Gastroenterol Hepatol. 2003 Jul;18(7):803-8
12795752
J Mol Biol. 1982 May 5;157(1):105-32
7108955
J Physiol. 2002 Jul 1;542(Pt 1):3-16
12096044
J Exp Biol. 2001 Jun;204(Pt 11):1831-44
11441026
Dig Dis Sci. 2000 Jan;45(1):1-6
10695605
J Comp Physiol B. 2008 Feb;178(2):149-56
17768629
J Physiol. 1999 Jan 1;514 ( Pt 1):211-27
9831728
Pflugers Arch. 1999 Jun;438(1):94-100
10370092
Proc Natl Acad Sci U S A. 1999 Aug 31;96(18):10261-6
10468596
FEBS Lett. 2003 Apr 10;540(1-3):157-62
12681500
Neurosci Lett. 2006 Mar 13;395(3):206-10
16309835
Syst Biol. 2001 Jun;50(3):367-90
12116581
Histochem Cell Biol. 2004 Jun;121(6):463-71
15221416
Am J Physiol. 1999 Mar;276(3):C621-7
10069989
Proc Natl Acad Sci U S A. 1993 Aug 1;90(15):7275-9
8346245
Comp Biochem Physiol A Mol Integr Physiol. 2007 Oct;148(2):430-44
17618150
J Mol Histol. 2005 Feb;36(1-2):1-14
15703994