Intectin, a novel small intestine-specific glycosylphosphatidylinositol-anchored protein, accelerates apoptosis of intestinal epithelial cells.
Intestinal epithelial cells undergo rapid turnover and exfoliation especially at the villus tips. This process is modulated by various nutrients especially fat. Apoptosis is one of the important regulatory mechanisms of this turnover. Therefore, identification of the factors that control epithelial cell apoptosis should help us understand the mechanism of intestinal mucosal turnover. Here, we report the identification of a novel small intestine-specific member of the Ly-6 family, intectin, by signal sequence trap method. Intectin mRNA expression was exclusively identified in the intestine and localized at the villus tips of intestinal mucosa, which is known to undergo apoptosis. Intectin mRNA expression was modulated by nutrition. Intestinal epithelial cells expressing intectin were more sensitive to palmitate-induced apoptosis, compared with control intestinal epithelial cells, and such effect was accompanied by increased activity of caspase-3. Intectin expression also reduced cell-cell adhesion of intestinal epithelial cells.
Kitazawa
Hidefumi
H
Department of Medicine and Pathophysiology, Graduate School of Frontier Bioscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
Nishihara
Tamao
T
Nambu
Tadahiro
T
Nishizawa
Hitoshi
H
Iwaki
Masanori
M
Fukuhara
Atsunori
A
Kitamura
Toshio
T
Matsuda
Morihiro
M
Shimomura
Iichiro
I
D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis; D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D003001:Cloning, Molecular; D003600:Cytosol / Q000378:metabolism; D018076:DNA, Complementary / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004847:Epithelial Cells / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism; D005822:Genetic Vectors; D017261:Glycosylphosphatidylinositols / Q000737:chemistry*; D017403:In Situ Hybridization; D007413:Intestinal Mucosa / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008562:Membrane Glycoproteins / Q000737:chemistry* / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D019308:Palmitic Acid / Q000737:chemistry; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013347:Subcellular Fractions; D013997:Time Factors; D014018:Tissue Distribution
D018076:DNA, Complementary; D017261:Glycosylphosphatidylinositols; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; C493172:intectin protein, mouse; D019308:Palmitic Acid; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases