Permanent URL to this publication: http://dx.doi.org/10.5167/uzh-2771
Lundquist, P; Murer, H; Biber, J (2007). Type II Na+-Pi cotransporters in osteoblast mineral formation: Regulation by inorganic phosphate. Cellular Physiology and Biochemistry, 19(1-4):43-56.
- Registered users only
During calcification of bone, large amounts of phosphate (P(i)) must be transported from the circulation to the osteoid. Likely candidates for osteoblast P(i) transport are the type II sodium-phosphate cotransporters NaPi-IIa and NaPi-IIb that facilitate transcellular P(i) flux in kidney and intestine, respectively. We have therefore determined the 'cotransporters' expression in osteoblast-like cells. We have also studied the 'cotransporters' regulation by P(i) and during mineralization in vitro. Phosphate uptake and cotransporter protein expression was investigated at early, late and mineralizing culture stages of mouse (MC3T3-E1) and rat (UMR-106) osteoblast-like cells. Both NaPi-IIa and NaPi-IIb were expressed by both osteoblast-like cell lines. NaPi-IIa was upregulated in both cell lines one week after confluency. After 7 days in 3mM P(i) NaPi-IIa was strongly upregulated in both cell lines. NaPi-IIb expression was unaffected by both culture stage and P(i) supplementation. The expression of both cotransporters was unaffected by P(i) deprivation. In vitro mineralization at 1.5mM P(i) was preceded by a three-fold increase in osteoblast sodium-dependent P(i) uptake and a corresponding upregulation of both NaPi-IIa and NaPi-IIb. Their expression thus seem regulated by phosphate in a manner consistent with their playing a role in transcellular P(i) flux during mineralization. Copyright 2007 S. Karger AG, Basel.
|Item Type:||Journal Article, refereed, original work|
|Communities & Collections:||04 Faculty of Medicine > Center for Integrative Human Physiology
04 Faculty of Medicine > Institute of Physiology
07 Faculty of Science > Institute of Physiology
|DDC:||570 Life sciences; biology
610 Medicine & health
|Deposited On:||29 Jul 2008 13:20|
|Last Modified:||29 Nov 2013 20:06|
|Citations:||Web of Science®. Times Cited: 19|
Scopus®. Citation Count: 21
Users (please log in): suggest update or correction for this item
Repository Staff Only: item control page