Differential expression patterns of claudins, tight junction membrane proteins, in mouse nephron segments.
As the first step in understanding the physiologic functions of claudins (tight junction integral membrane proteins) in nephrons, the expression of claudin-1 to -16 in mouse kidneys was examined by Northern blotting. Among these claudins, only claudin-6, -9, -13, and -14 were not detectable. Claudin-5 and -15 were detected only in endothelial cells. Polyclonal antibodies specific for claudin-7 and -12 were not available. Therefore, the distributions of claudin-1, -2, -3, -4, -8, -10, -11, and -16 in nephron segments were examined with immunofluorescence microscopy. For identification of individual segments, antibodies specific for segment markers were used. Immunofluorescence microscopic analyses of serial frozen sections of mouse kidneys with polyclonal antibodies for claudins and segment markers revealed that claudins demonstrated very complicated, segment-specific, expression patterns in nephrons, i.e., claudin-1 and -2 in Bowman's capsule, claudin-2, -10, and -11 in the proximal tubule, claudin-2 in the thin descending limb of Henle, claudin-3, -4, and -8 in the thin ascending limb of Henle, claudin-3, -10, -11, and -16 in the thick ascending limb of Henle, claudin-3 and -8 in the distal tubule, and claudin-3, -4, and -8 in the collecting duct. These segment-specific expression patterns of claudins are discussed, with special reference to the physiologic functions of tight junctions in nephrons.
Kiuchi-Saishin
Yumiko
Y
*Department of Cell Biology, Kyoto University Faculty of Medicine, Kyoto, Japan; Department of Ophthalmology, Osaka University Medical School, Osaka, Japan; and Shirakawa Institute of Animal Genetics, Fukushima, Japan.
Gotoh
Shimpei
S
*Department of Cell Biology, Kyoto University Faculty of Medicine, Kyoto, Japan; Department of Ophthalmology, Osaka University Medical School, Osaka, Japan; and Shirakawa Institute of Animal Genetics, Fukushima, Japan.
Furuse
Mikio
M
*Department of Cell Biology, Kyoto University Faculty of Medicine, Kyoto, Japan; Department of Ophthalmology, Osaka University Medical School, Osaka, Japan; and Shirakawa Institute of Animal Genetics, Fukushima, Japan.
Takasuga
Akiko
A
*Department of Cell Biology, Kyoto University Faculty of Medicine, Kyoto, Japan; Department of Ophthalmology, Osaka University Medical School, Osaka, Japan; and Shirakawa Institute of Animal Genetics, Fukushima, Japan.
Tano
Yasuo
Y
*Department of Cell Biology, Kyoto University Faculty of Medicine, Kyoto, Japan; Department of Ophthalmology, Osaka University Medical School, Osaka, Japan; and Shirakawa Institute of Animal Genetics, Fukushima, Japan.
Tsukita
Shoichiro
S
*Department of Cell Biology, Kyoto University Faculty of Medicine, Kyoto, Japan; Department of Ophthalmology, Osaka University Medical School, Osaka, Japan; and Shirakawa Institute of Animal Genetics, Fukushima, Japan.
D000818:Animals; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D009399:Nephrons / Q000378:metabolism*; D020033:Protein Isoforms / Q000378:metabolism; D019108:Tight Junctions / Q000378:metabolism*; D014018:Tissue Distribution
D008565:Membrane Proteins; D020033:Protein Isoforms