WW Domain Containing Transcription Regulator regulates human conjunctiva epithelial cell proliferation via inhibiting TGFβ signaling pathway [corrected].
OBJECTIVE
To investigate the role of Tafazzin (TAZ) protein in regulating the proliferation of normal human conjunctiva epithelial cells and epithelial cells from pterygium tissue.


METHODS
Conjunctiva epithelial cells were cultured in keratinocytes growth medium and treated with transformation growth factor β (TGFβ) to analyze the expression and translocation of TAZ protein by immunostaining and BrdU analysis. Immortalized conjunctiva epithelial cells (NHC) were treated with TGFβ, targeting siRNA, TGFβ receptor antibody or TGFβ receptor inhibitor, to study the involvement of TAZ and TGFβ signaling pathway in conjunctiva cell proliferation by cell adhesion assay. Conjunctiva tissues from a normal human eye and an eye with pterygium disease were collected for histological analyses and western blot to evaluate the TAZ protein expression in vivo.


RESULTS
TAZ expression was upregulated in mitotic conjunctiva epithelial cells, proliferating conjunctiva epithelial cells, TGFβ treated conjunctiva epithelial cells and human pterygium epithelium. TAZ siRNA induced less conjunctiva epithelial cell growth. Moreover, TGFβ receptor antibody and TGFβ receptor inhibitor rescued this anti-proliferative effect of TAZ siRNA.


CONCLUSIONS
TAZ is involved in human conjunctiva epithelial cells proliferation via regulating TGFβ signaling pathway.
Singapore Eye Research Institute, Singapore.
Xiao Wei
XW
Tan
Roger W
RW
Beuerman
Chye Khoon
CK
Poh
Jodhbir S
JS
Mehta
D000217:Acyltransferases; D000906:Antibodies / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D003228:Conjunctiva / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D008938:Mitosis / Q000235:genetics; D061251:Primary Cell Culture; D021381:Protein Transport / Q000187:drug effects; D011625:Pterygium / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D034741:RNA, Small Interfering / Q000235:genetics; D018125:Receptors, Transforming Growth Factor beta / Q000037:antagonists & inhibitors / Q000235:genetics; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000494:pharmacology
D000906:Antibodies; D034741:RNA, Small Interfering; D018125:Receptors, Transforming Growth Factor beta; D014157:Transcription Factors; D016212:Transforming Growth Factor beta; D000217:Acyltransferases; C108675:TAFAZZIN protein, human