Dual effects of the membrane-anchored MMP regulator RECK on chondrogenic differentiation of ATDC5 cells.
Extracellular matrix (ECM) undergoes continuous remodeling during mammalian development. Although involvement of matrix metalloproteinases (MMPs) in ECM degradation has been well documented, how this process is regulated to allow proper ECM accumulation remains unclear. We previously showed the involvement of a membrane-anchored MMP regulator, RECK (reversion-inducing cysteine-rich protein with Kazal motifs), in vascular development in mice. Here we report that Reck mRNA can be detected in developing cartilage in E13.5 approximately 16.5 mouse embryos and is progressively upregulated during differentiation of a chondrogenic cell line ATDC5 in vitro. In the early phase of ATDC5 differentiation, RECK expression stays low, multiple MMPs are upregulated, and there is ECM degradation at the sites of cellular condensation. In the later phase, RECK is upregulated inside the expanding cartilaginous nodules where type II collagen is accumulated while active ECM degradation persists along the rim of the nodules. Constitutive RECK expression suppressed initial cellular condensation, whereas RECK knockdown suppressed the later ECM accumulation in the cartilaginous nodules. These results suggest that RECK expression at the right place (in the core of the nodules) and at the right time (only in the later phase) is important for proper chondrogenesis and that RECK, together with MMPs, plays a crucial role in regulating dynamic processes of tissue morphogenesis.
Kondo
Shunya
S
Department of Molecular Oncology, Kyoto University Graduate School of Medicine, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan.
Shukunami
Chisa
C
Morioka
Yoko
Y
Matsumoto
Naoya
N
Takahashi
Rei
R
Oh
Junseo
J
Atsumi
Tadao
T
Umezawa
Akihiro
A
Kudo
Akira
A
Kitayama
Hitoshi
H
Hiraki
Yuji
Y
Noda
Makoto
M
D000818:Animals; D002356:Cartilage / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics*; D002460:Cell Line; D019902:Chondrocytes / Q000166:cytology* / Q000378:metabolism; D003094:Collagen / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism; D019084:Fluorescent Antibody Technique, Indirect; D058851:GPI-Linked Proteins; D020869:Gene Expression Profiling; D020868:Gene Silencing; D015151:Immunoblotting; D017403:In Situ Hybridization; D020782:Matrix Metalloproteinases / Q000378:metabolism* / Q000502:physiology; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D051379:Mice; D009154:Mutation / Q000235:genetics / Q000502:physiology
D058851:GPI-Linked Proteins; D008562:Membrane Glycoproteins; C492025:Reck protein, mouse; D003094:Collagen; D020782:Matrix Metalloproteinases