Fig. 4

a The diagram illustrates the DNB ranking during the critical transition of osteoporosis based on network degrees and pathway hits. b, c Volcano plot of differentially expressed genes between primary osteoporosis patients and middle-aged/elderly healthy donors. d The relative expression level of representative osteoporosis-associated genes was validated by quantitative real-time polymerase chain reaction (qRT‒PCR) in the wild-type (WT) and DEX-treated zebrafish (n = 20). e Diagram of the cdkn1a-targeting gRNA sequences. CGG, GGG, TGG and CCC (green) are the protospacer adjacent motif (PAM) sequences. Arrows indicate primer positions. f In cdkn1a crispant zebrafish, representative Sanger sequencing results of the PCR amplicons from 14 individual embryos showed different out-of-frame and in-frame indel mutations induced by Cas9/sgRNA in the targeted sites. Substitutions are represented in purple, deletions are indicated by purple strikethroughs, and insertions are highlighted in green. g, h The relative expression levels of cdkn1a were validated by qRT‒PCR in the WT, cdkn1a^Cas9/sgRNA, and cdkn1a^mRNA-treated larvae (n = 20). *P < 0.05, **P < 0.01, ****P < 0.0001, Student’s t-test.