The pro-a2(XI) collagen gene is expressed in odontoblasts

• Published in: Biochemical and biophysical research communications Vol. 392; no. 2; pp. 166 - 170
• Main Authors: Hamada, Yasuhide, Sumiyoshi, Hideaki, Matsuo, Noritaka, Yun-Feng, Wu, Nakashima, Momoko, Yanagisawa, Shigetaka, Yoshioka, Hidekatsu
• Format: Journal Article
• Language: English
• Published: 05.02.2010
• ISSN: 0006-291X
• DOI: 10.1016/j.bbrc.2010.01.001

Since the dentine is analogous to bone, its extracellular matrix shares many similarities to bone tissues. Similar to the bone, type I collagen is the major organic component in dentine. However, little is known about minor fibrillar collagens, which seem to be co-expressed such as type I or II collagen. The present study examined the gene expression of type V and XI collagens, which play important roles in collagen fibril formation and skeletal morphogenesis, using RT-PCR and in situ hybridization combined with immunohistochemistry. The transcripts of pro-a1(XI), pro-a2(XI), pro-a1(V) and pro-a2(V) chains were present, but not pro-a3(V) and pro-a1(II) chains, of which an overglycosylated variant is pro-a3(XI) chain, in mouse incisor tooth, using RT-PCR and in situ hybridization. The pro-a2(XI) protein, which is mainly expressed in cartilage, were observed in the odontoblast using a specific polyclonal antibody. Real-time RT-PCR showed that the transcripts of pro-a2(XI), pro-a1(V) and pro-a2(V) were predominant in crown and that of pro-a1(XI) in root of the tooth. Finally, the expression of pro-a2(XI) was confirmed with an odontoblastic cell line transformed with human telomerase reverse transcriptase (hTERT) both in vitro and in vivo. The data suggest a new subtype of the V/XI collagen molecule containing a2(XI) chain.