TRIM21 and osteoporosis: For further elucidation of the role of Trim21 in osteoanabolic function in pathological bone loss, Trim21+/+ and Trim21−/− mice were sham-operated or underwent an OVX at 12 weeks of age to mimic estrogen deficiency-induced osteoporosis, followed by histological and micro-CT analysis 8 weeks later (Fig. S9a).