Pitx2, a beta-catenin-regulated transcription factor, regulates the differentiation of outer root sheath cells cultured in vitro.
BACKGROUND
Beta-catenin exerts its crucial role in hair follicle development and hair growth cycle. Although the importance of Wnt/beta-catenin is well recognized, the downstream effectors of beta-catenin have not been clearly elucidated yet.


OBJECTIVE
The aim of this study is to identify the beta-catenin-regulated genes in cultured human hair outer root sheath (ORS) cells.


METHODS
We transduced ORS cells with adenovirus harboring the expression cassette for constitutive active form of beta-catenin, then performed cDNA microarray.


RESULTS
Overexpression of beta-catenin led to the upregulation of hair cell differentiation markers such as keratin 16 and 17. In addition, the expression of Pitx2, a bicoid-type homeodomain transcription factor, was also increased by overexpression of beta-catenin in ORS cells cultured in vitro. To investigate the potential role of Pitx2, we made the recombinant adenovirus expressing Pitx2, then transduced into the cultured ORS cells. Interestingly, Pitx2 induced the expression of keratin 16 and 17, indicating that Pitx2 activates ORS cells towards the follicular differentiation pathway preferentially.


CONCLUSIONS
Our results implicate the potential importance of Pitx2 as a beta-catenin downstream modulator in hair growth control.
Sohn
Kyung-Cheol
KC
Department of Dermatology and Research Institute for Medical Sciences, School of Medicine, Chungnam National University, 55 Munhwa-ro, Daejeon 301-747, Republic of Korea.
Shi
Ge
G
Jang
Sunhyae
S
Choi
Dae-Kyoung
DK
Lee
Young
Y
Yoon
Tae-Jin
TJ
Park
Hwayong
H
Hwang
Chul
C
Kim
Hyoung Joo
HJ
Seo
Young-Joon
YJ
Lee
Jeung-Hoon
JH
Park
Jang-Kyu
JK
Kim
Chang Deok
CD
D002454:Cell Differentiation / Q000235:genetics / Q000502:physiology*; D002478:Cells, Cultured; D018859:Hair Follicle / Q000166:cytology / Q000378:metabolism*; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D053536:Keratin-16 / Q000235:genetics / Q000378:metabolism*; D053537:Keratin-17 / Q000235:genetics / Q000378:metabolism*; D015603:Keratinocytes / Q000166:cytology / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism*; D000097577:Homeobox Protein PITX2
D018398:Homeodomain Proteins; D053536:Keratin-16; D053537:Keratin-17; D014157:Transcription Factors; D051176:beta Catenin; D000097577:Homeobox Protein PITX2