Osmotic Shock Protein
نویسندگان
چکیده
Purpose. Bovine lens epithelial cells (BLECs) accumulate osmotically active organic solutes (i.e., osmolytes) including myo-inositol when exposed to hypertonic stress (osmotic shock). In hypertonic medium, the increase in myo-inositol accumulation is attributed to an elevation in activity of Na/myo-inositol cotransporter(s). The authors report the nature of the hypertonicity-induced enhancement of myo-inositol uptake in cultured BLECs by amplifying a 626 bp cDNA from lens cell RNA. Methods. A portion of cDNA encoding a Na/myo-inositol cotransporter was isolated from cultured BLECs using PCR primers designed from an established myo-inositol transporter from Madin-Darby canine kidney (MDCK) cells. Using the reverse transcription-polymerase chain reaction, a 626 bp PCR product was amplified. Its nucleic acid sequence was determined by the dideoxynucleotide method using Sequenase kit. Na/Myo-inositol cotransporter mRNA expression in the cultured cells was demonstrated under physiological and hypertonic conditions by northern analysis of poly (A) RNA using the lens cell 626 bp cDNA as probe.
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