Fig. 3

HOTAIR overexpression in osteoblasts increases bone formation. a Schematic representation of the transgenic construct used to generate osteoblast-specific HOTAIR overexpression transgenic mouse lines. b qRT‒PCR analysis of HOTAIR levels in bone and other tissues from 6-month-old WT and osteoblast-specific HOTAIR-overexpressing mice (Bglap-HOTAIR TG) (n = 6). c Representative images showing three-dimensional trabecular architecture by micro-CT reconstruction at 6 months of age. Scale bar, 0.5 mm. d Representative images showing the three-dimensional trabecular architecture and cortical architecture as shown by micro-CT reconstruction at the distal femurs at 6 months of age. Scale bar, 0.5 mm. e Micro-CT measurements of BV/TV, BMD, Tb.N, Tb.Th, Tb.Sp, and Cort.Th in the distal femurs of mice (n = 10 for each group). f Representative images showing new bone formation assessed by double calcein labeling. Scale bar, 20 μm. g Quantification of mineral apposition rate (MAR) and osteoblast number to bone surface (N.ob/BS) (n = 6 for each group). h The maximal (max.) load at failure determined by three-point bending of femurs from WT (n = 10) and Ocn-HOTAIR TG (n = 10) mice. i Histological images for Ocn staining of the proximal tibia. Scale bar, 100 μm. j ELISA analysis of the PINP protein level in the serum from WT (n = 10) and Bglap-HOTAIR TG (n = 10) mice. k qRT-PCR analysis of Alp, Bglap and Col1a1 mRNA levels in bone tissues collected from WT (n = 10) and Bglap-HOTAIR TG (n = 10) mice. Two-tailed unpaired Student’s t test was used for statistical evaluations of two group comparisons. All data are the mean ± s.e.m. *P < 0.05, **P < 0.01, ***P < 0.001