Naslov
Immunolocalization of Na+-independent sulfate transporter Sat-1 (Slc26a1) in rat kidney and gastrointestinal tract

Autori
Brzica, Hrvoje ; Balen, Daniela ; Breljak, Davorka ; Ljubojević, Marija ; Žlender, Vilim ; Burckhardt, Birgitta C. ; Burckhardt, Gerhard ; Sabolić, Ivan

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Periodicum Biologorum ; Final Programme and Abstract Book / Banfić, H. ; Boban, M. ; Francetić, i. ; Klarica, M. ; Muck-šeler, D. ; Pivac, N. ; Sabolić, I. ; Tvrdeić, A. ; Župan, G. - Zagreb : Hrvatsko prirodoslovno društvo, 2007, Vol. 109, 148-148

Skup
5th Croatian Congress of Pharmacology and 2nd Congress of Croatian Physiological Society with international participation

Mjesto i datum
Osijek, Hrvatska, 19.09.2007. - 22.09.2007

Vrsta sudjelovanja
Poster

Vrsta recenzije
Domaća recenzija

Ključne riječi
Sat-1; rat; kidney; gastrointestinal tract; mitochondria

Sažetak
The Na+-independent sulfate (S) transporter Sat-1 has been localized to the basolateral membrane (BLM) of proximal tubules in the rat kidney (K). The same transporter may also mediate S transport in the gastrointestinal tract (GIT) and liver (L), but its presence and the exact cellular localization in these organs has not been described. In this work we used a monoclonal antibody to Sat-1 protein (Sat-1-Ab) and performed localization studies by immunofluorescence cytochemistry (IC) and Western blotting (WB) in the L and in various GIT segments in rats. The Sat-1-Ab was verified in the K by achieving a positive staining of BLM in the proximal tubule S1 and S2 segments, and by labeling a single, ~85 kDa protein band in BLM isolated from renal cortical homogenate. In the L, the Sat-1-Ab strongly stained the sinusoidal membrane ; the canalicular membrane and other structures in hepatocytes remained unstained. However, the double staining in various GIT segments with the Sat-1-Ab and a polyclonal antibody to cell adhesion molecule 105 (CAM-105) indicated the localization of Sat-1 in an intracellular vesicular compartment. In the tested GIT segments, the intensity of intracellular Sat-1 staining showed the following pattern: esophagus < duodenum < jejunum < ileum < colon < stomach. The localization of Sat-1 in endocytic vesicles was disproven by an in vivo assay of FITC-dextran uptake in the colon cells, whereas the double-staining for Sat-1 and the mitochondrial marker cytochrome C in the colon and stomach revealed a complete colocalization of these proteins in mitochondria of enterocytes (colon) and oxyntic cells (stomach). However, in WB of total cell membranes, isolated from the L and various GIT segments, the Sat-1-Ab labeled weakly the ~40 kDa protein band, whereas the K-specific 85 kDa protein band was not labeled at all in these membranes. We conclude that in the rat L and GIT cells, the Sat-1 protein is different from that in the K and may exist as a shorter (truncated) isoform. In various GIT cells, the transporter may be localized in mitochondria.

Izvorni jezik
Engleski

Znanstvena područja
Temeljne medicinske znanosti

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