Expression data from primary osteoblasts isolated from calvaria of Gnptab(c.3082insC) knock-in mice compared with osteoblasts isolated from wild-type littermates

Mucolipidosis type II (MLII) is a severe inherited multisystemic disorder caused by mutations in the GNPTAB gene. Skeletal abnormalities are a predominant feature of MLII. Here we investigate the gene expression in a knock-in mouse model for mucolipidosis type II, generated by the insertion of a cytosine in the murine Gnptab gene (c.3082insC) that is homologous to a homozygous mutation in an MLII patient. Since osteoblasts are critically involved in regulating bone development and remodeling, a genome-wide expression analysis was performed with RNA isolated from primary cultures of osteoblasts originating from MLII knock-in mice (KI) compared to RNA from wild-type (WT) osteoblasts to identify dysregulated genes involved in pathogenic mechanisms. Primary osteoblasts were isolated from calvaria of 5-day-old wild-type (WT) and MLII knock-in littermates (KI). RNA was extracted at day 10 of differentiation induced by ascorbic acid and beta-glycerophosphate and hybridization on Affymetrix microarrays. We used preparations of RNA from two individual primary cultures of osteoblasts for every genotype (WT_OB_I, WT_OB_II, KI_OB_I, KI_OB_II) and compared WT vs KI samples.