Gene expression analysis of ER-stressed growth plate chondrocytes in two mouse models of Schmid chondrodysplasia

ABSTRACT: We set out to generate transcriptional maps of chondrocyte UPR gene networks in vivo using two mouse models (Schmid and Cog) of Schmid chondrodysplasia, in order to define the consequences of UPR activation for the adaptation, differentiation, and survival of chondrocytes experiencing ER stress during hypertrophy, thus providing insights into ER stress signaling and its impact on cartilage pathophysiology. Our data demonstrate that both models displayed similar unfolded protein responses (UPRs), involving activation of ER stress sensors Ire1 and Atf6 and upregulation of their downstream targets, including molecular chaperones, foldases, and ER-associated degradation machinery. Also upregulated were the emerging UPR regulators Wfs1 and Syvn1, recently identified UPR components including Armet and Creld2, and genes not previously implicated in ER stress such as Steap1 and Fgf21. Moreover, we transcriptionally profiled the expression of wildtype growth plate zone gene signatures in the mutant hypertrophic zones, in order to define the differentiation status of ER-stressed chondrocytes in the mutant hypertrophic zones. Hypertrophic zone gene upregulation and proliferative zone gene downregulation were both inhibited in Schmid hypertrophic zones, resulting in the persistence of a proliferative chondrocyte-like expression profile in ER-stressed Schmid chondrocytes. For the mutant hypertrophic zone gene expression profiling, the hypertrophic zone from one tibia from each of three two week old Schmid, wildtype (Schmid background), Cog, and wildtype (Cog background) mice was microdissected. In all cases, total RNA was extracted and amplified through two rounds of linear amplification, labelled with Cy3, and interrogated by microarray analysis using the Agilent 44K, mouse whole genome platform.

ORGANISM(S): Mus musculus

SUBMITTER: Trevor Cameron 

PROVIDER: E-GEOD-30628 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress