Expression of UNCL during development of periodontal tissue and response of periodontal ligament fibroblasts to mechanical stress in vivo and in vitro.
Mutations in two genes, uncoordinated (unc) and uncoordinated-like (uncl), lead to a failure of mechanotransduction in Drosophila. UNCL, the human homolog of unc and uncl, is preferentially expressed in periodontal ligament (PDL) fibroblasts compared with gingival fibroblasts. However, the precise role of UNCL in the PDL remains unclear. The aim of the present study has been to examine whether mechanical stimuli modulate the expression of UNCL in the human PDL in vivo and in vitro and to examine the roles of UNCL in the development, regeneration, and repair of the PDL. We have investigated the expression pattern of UNCL during the development of periodontal tissue and the response of PDL fibroblasts to mechanical stress in vivo and in vitro. The expression of UNCL mRNA and protein increases with PDL fibroblast differentiation from the confluent to multilayer stage but slightly decreases on mineralized nodule formation. UNCL has also been localized in ameloblasts and adjacent cells, differentiating cementoblasts, and osteoblasts of the developing tooth. Strong distinct UNCL expression has further been observed in the differentiating cementoblasts of the tooth periodontium at the site of tension after orthodontic tooth movement. Application of cyclic mechanical stress on PDL fibroblasts increases the expression of UNCL mRNA. These results indicate that UNCL plays important roles in the development, differentiation, and maintenance of periodontal tissues and also suggest a potential role of UNCL in the mechanotransduction of PDL fibroblasts.
Kim
Heung-Joong
HJ
Oral Biology Research Institute, College of Dentistry, Chosun University, Gwang-Ju, South Korea.
Choi
Yong Seok
YS
Jeong
Moon-Jin
MJ
Kim
Byung-Ock
BO
Lim
Sung-Hoon
SH
Kim
Do Kyung
DK
Kim
Chong Kwan
CK
Park
Joo-Cheol
JC
D000818:Animals; D002454:Cell Differentiation; D002478:Cells, Cultured; D003739:Dental Cementum / Q000166:cytology / Q000378:metabolism*; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D015870:Gene Expression / Q000502:physiology; D006801:Humans; D008297:Male; D040542:Mechanotransduction, Cellular / Q000502:physiology*; D008565:Membrane Proteins / Q000235:genetics*; D010513:Periodontal Ligament / Q000166:cytology / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012038:Regeneration; D013314:Stress, Mechanical; D014945:Wound Healing / Q000502:physiology
D008565:Membrane Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C416052:Unc50 protein, rat