Na(+)/I(-) symporter and Pendred syndrome gene and protein expressions in human extra-thyroidal tissues.
OBJECTIVE
The expression of two recently identified iodide transporters, namely the sodium/iodide symporter (NIS) and pendrin, the product of the gene responsible for the Pendred syndrome (PDS), was studied in a series of various extra-thyroidal human tissues, and especially in those known to concentrate iodide.


METHODS
To this end, we used real-time kinetic quantitative PCR to detect NIS and PDS transcripts and immunohistochemistry for the analysis of their protein products.


RESULTS
NIS gene and protein expression was detected in most tissues known to concentrate iodine, and particularly in salivary glands and stomach. In contrast, PDS gene expression was restricted to a few tissues, such as kidney and Sertoli cells. Interestingly, in kidney, pendrin immunostaining was detected at the apical pole of epithelial cells of the thick ascending limb of the Henle's loop and of the distal convoluted tubule.


CONCLUSIONS
This study provides new insights on the localization and expression of two genes involved in iodide transport and emphasizes the interest of combining real-time quantitative PCR and immunohistochemistry for the comparison of gene and protein expression in tissues.
Department of Clinical Biology, Institut Gustave-Roussy, 94805 Villejuif, France.
L
L
Lacroix
C
C
Mian
B
B
Caillou
M
M
Talbot
S
S
Filetti
M
M
Schlumberger
J M
JM
Bidart
D001692:Biological Transport; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D016764:Cell Polarity; D004064:Digestive System / Q000378:metabolism*; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism; D020869:Gene Expression Profiling; D006801:Humans; D007150:Immunohistochemistry; D007454:Iodides / Q000378:metabolism*; D007668:Kidney / Q000166:cytology / Q000378:metabolism; D007700:Kinetics; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D026901:Membrane Transport Proteins; D009928:Organ Specificity; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012469:Salivary Glands / Q000378:metabolism; D012708:Sertoli Cells / Q000378:metabolism; D000076988:Sulfate Transporters; D027981:Symporters; D013577:Syndrome; D013961:Thyroid Gland / Q000378:metabolism; D000099209:Sodium-Iodide Symporters
D002352:Carrier Proteins; D007454:Iodides; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D012333:RNA, Messenger; D000076988:Sulfate Transporters; D027981:Symporters; D000099209:Sodium-Iodide Symporters; C085609:SLC26A4 protein, human