Expression data of bone marrow-derived osteoclasts expressing wild-type or mutant PSS1

Phosphatidylserine (PS) is an acidic phospholipid that is involved in various cellular events. Heterologous dominant mutations have been identified in the gene encoding PS synthase 1 (PSS1) in patients of a congenital disease called Lenz-Majewski syndrome (LMS). LMS patients show various symptoms, including craniofacial/distal-limb bone dysplasia and progressive hyperostosis. The LMS-causing gain-of-function mutants of PSS1 (PSS1-LMS) have been shown to synthesize PS without control, but why the uncontrolled synthesis would lead to LMS is unknown. We investigated the effect of PSS1-LMS(Q353R) on osteoclasts to elucidate the causative mechanism of LMS and found that PSS1-LMS inhibited the formation, multinucleation, and activity of osteoclasts. We used microarrays to comprehensively examine the effects of PSS1-LMS on osteoclast gene expression. Bone marrow cells were treated with MCSF alone or MCSF and RANKL and infected one day later with a retroviral vector expressing wild-type or mutant PSS1. Cells were collected for microarray analysis on days 3 and 6 after MCSF/RANKL treatment.