Lineage tracing using matrilin-1 gene expression reveals that articular chondrocytes exist as the joint interzone forms.
We have developed a mouse in which the Cre recombinase gene has been targeted to exon 1 of the matrilin-1 gene (Matn1) to investigate the origins of articular chondrocytes and the development of the knee joint. Analysis of joints from offspring of Matn1-Cre/R26R crosses demonstrated that articular chondrocytes are derived from cells that have never expressed matrilin-1 whereas the remainder of the chondrocytes in the cartilage anlagen expresses matrilin-1. A band of chondrocytes adjacent to the developing interzone in the E13.5 day knee joint became apparent because these chondrocytes did not turn on expression of matrilin-1 in contrast to the other chondrocytes of the anlagen. The chondrocytes of the presumptive articular surface therefore appear to arise directly from a subpopulation of early chondrocytes that do not activate matrilin-1 expression rather than by redifferentiation from the flattened cells of the interzone. In addition, lineage tracing using both Matn1-Cre/R26R and Col2a1-Cre/R26R lines indicated that non-cartilaginous structures in the knee such as cruciate ligament, synovium and some blood vessels are formed by cells derived from the early chondrocytes of the anlagen.
Hyde
Gareth
G
Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, The University of Manchester, Manchester M13 9PT, UK.
Dover
Sharon
S
Aszodi
Attila
A
Wallis
Gillian A
GA
Boot-Handford
Raymond P
RP
D000818:Animals; D000831:Animals, Newborn; D002358:Cartilage, Articular / Q000166:cytology / Q000196:embryology / Q000254:growth & development; D002454:Cell Differentiation; D019070:Cell Lineage / Q000502:physiology*; D019902:Chondrocytes / Q000166:cytology* / Q000378:metabolism; D005091:Exons; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis* / Q000235:genetics; D006023:Glycoproteins / Q000096:biosynthesis* / Q000235:genetics; D007596:Joints / Q000166:cytology* / Q000196:embryology / Q000254:growth & development; D064235:Matrilin Proteins; D051379:Mice; D008822:Mice, Transgenic; D013583:Synovial Membrane / Q000166:cytology / Q000196:embryology / Q000254:growth & development
D016326:Extracellular Matrix Proteins; D006023:Glycoproteins; C577540:Matn1 protein, mouse; D064235:Matrilin Proteins