Anat Cell Biol.  2012 Sep;45(3):155-159. 10.5115/acb.2012.45.3.155.

TonEBP and SMIT expression in human placenta

• Shin JA
• Kwon HM
• Han KH
• Lee HY

• KMID: 2046742
• DOI: http://doi.org/10.5115/acb.2012.45.3.155

Abstract

Tonicity-responsive enhancer binding protein (TonEBP) is a signal transcription factor of transporters such as sodium-myo-inositol cotransporter (SMIT), aldose reductase. TonEBP has a variety of functions such as control of intracellular osmolytes and immunomodulating. It is known that TonEBP is abundant in the placenta, but location and function aren't known. The aim of this study is to describe the localization of TonEBP in the placenta. We assayed the immunohistochemistry of TonEBP and performed in situ hybridization of SMIT in normal human full term placenta. In normal human full term placenta, TonEBP was in villous trophoblasts, extravillous trophoblasts and some endothelial cells. The result of the in situ hybridization of SMIT was similar to that of immunohistochemistry of TonEBP. Neither TonEBP nor SMIT was present in TonEBP knockout mouse placenta. This shows TonEBP is a key factor in SMIT transcription. TonEBP may play an important role in transporting of inositol to fetus in placenta.

Keyword

TonEBP; NFAT5; Sodium-myo-inositol cotransporter; Human placenta

MeSH Terms

Aldehyde Reductase
Animals
Carrier Proteins
Endothelial Cells
Fetus
Humans
Immunohistochemistry
In Situ Hybridization
Inositol
Mice
Mice, Knockout
Placenta
Transcription Factors
Trophoblasts
Aldehyde Reductase
Carrier Proteins
Inositol
Transcription Factors

Figure

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  Fig. 1 Immunohistochemical localization of tonicity-responsive enhancer binding protein (TonEBP) in human placenta. (A) Nuclear staining of TonEBP was mainly in the villous trophoblasts (arrows). Some endothelial cells and connective cells were weakly stained. (B) TonEBP stained cell mass was showed in the basal plate (arrows). (C) Nuclear TonEBP stained cells (brown) were colocalized with cytokeratin 7 (blue). (D) Nuclear TonEBP stained cells (brown) were not colocalized with vimentin (blue). Serial 3 µm section of (C). (E) Negative control showed no labeling. Scale bars=50 µm (A-E).

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  Fig. 2 In situ hybridization of sodium-myo-inositol cotransporter (SMIT) in human placenta. (A, B) Cytoplasmic staining of SMIT antisense riboprobe was mainly in the villous trophoblast (arrows). Some endothelial cells and connective cells were weakly stained. (C) As a negative control, no specific staining of SMIT sense riboprobe was seen. Scale bars=50 µm (A-C).

• 

  Fig. 3 Immunohistochemical localization of tonicity-responsive enhancer binding protein (TonEBP) and in situ hybridization of sodium-myo-inositol cotransporter (SMIT) in TonEBP knockout mouse. (A) Nucleus of labyrinthin trophoblasts were stained for TonEBP immunohistochemistry in wild type mouse placenta (arrows). (B) No specific staining of TonEBP was seen in TonEBP knockout mouse placenta (arrowheads). (C) Cytoplasm of labyrinthin trophoblasts were stained for SMIT in situ hybridization in wild type mouse placenta (arrows). (D) No specific staining of SMIT was seen in TonEBP knockout mouse placenta (arrowheads). Scale bars=50 µm (A-D).

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