Molecular cloning and expression of a novel human aquaporin from adipose tissue with glycerol permeability.
In a systematic analysis of genes expressed in human adipose tissue, we detected a novel gene that is expressed uniquely in adipose tissue. The sequence showed that it encodes a 342-amino-acid protein containing six putative transmembrane domains, and is a new member of the aquaporin family of water-selective membrane channels. We named this gene aquaporin 9. It features a cyclic-AMP protein kinase phosphorylation consensus site in the NH3-terminal domain. Expression of the cRNA in Xenopus oocytes yielded a 7-fold increase in osmotic water permeability blocked by 0.3 mM HgCl2, and also facilitated the uptake of glycerol. Northern blot analysis demonstrated that the mRNA is abundant in adipose tissue, but not in other tissues. Thus, this gene product may participate in glycerol transport in adipocytes.
Kuriyama
H
H
Institute for Molecular and Cellular Biology, Osaka University, Osaka, Suita, 565, Japan.
Kawamoto
S
S
Ishida
N
N
Ohno
I
I
Mita
S
S
Matsuzawa
Y
Y
Matsubara
K
K
Okubo
K
K
D000273:Adipose Tissue / Q000378:metabolism*; D000328:Adult; D000595:Amino Acid Sequence; D000818:Animals; D051400:Aquaporin 3; D020346:Aquaporins; D001483:Base Sequence; D002463:Cell Membrane Permeability; D003001:Cloning, Molecular; D016384:Consensus Sequence; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D018076:DNA, Complementary; D005260:Female; D015723:Gene Library; D005990:Glycerol / Q000378:metabolism*; D006801:Humans; D007473:Ion Channels / Q000737:chemistry / Q000502:physiology; D008969:Molecular Sequence Data; D009865:Oocytes / Q000502:physiology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000096:biosynthesis; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014981:Xenopus
C496027:AQP3 protein, human; C109669:AQP9 protein, human; D020346:Aquaporins; D018076:DNA, Complementary; D007473:Ion Channels; D012333:RNA, Messenger; C108330:aquaporin 8; D051400:Aquaporin 3; D017868:Cyclic AMP-Dependent Protein Kinases; D005990:Glycerol