Phenotypic and transcriptomic analysis of growth plate in mice with abnormal cartilage-to-bone transition
PENG Xuanyi
SONG Shiju
LU Weiguang
FAN Jing
ZHENG Chao
YANG Liu
Abstract：Objective To investigate the effects of abnormal cartilage-to-bone transition on the cartilage phenotype and transcriptome in the mouse growth plate.Methods Col10a1-Cre;R26tdT/+mice enabling lineage tracing of hypertrophic chondrocytes or Col10a1-Cre mice were used as the control group.Meanwhile,Col10a1-Cre;R26DTA/+mice were constructed by conditionally overexpressing diphtheria toxin A(DTA)as the experimental group to observe the differences in growth and development status in mice with abnormal cartilage-to-bone transition.By observing the bone development phenotype in mice,the impact of abnormal cartilage-to-bone transition on osteochondral development in mice was clarified.Fluorescence staining of type Ⅱ collagen(COL-Ⅱ)of frozen sections and tartrate-resistant acid phosphatase(TRAP)staining of osteoclasts were performed to assess alterations in the growth plate extracellular matrix and osteoclast differentiation during abnormal cartilage-to-bone transition.Through transcriptomic sequencing analysis of the growth plate,the transcriptomic changes in the growth plate of Col10a1-Cre;R26DTA/+mice were elucidated.Results Compared with the control group,Col10a1-Cre;R26DrA/+mice exhibited a dwarf phenotype.COL-Ⅱ staining results demonstrated abnormal collagen accumulation in the growth plate of Col10a1-Cre;R26DTA/+mice.TRAP staining revealed a reduced number of osteoclasts in the ossification center,indicating impaired degradation of the growth plate extracellular matrix.Transcriptome sequencing data showed that after inducing abnormal cartilage-to-bone transition in mice with DTA,the expression of genes regulating osteoclast differentiation and angiogenesis in the growth plate was downregulated.Functional enrichment analysis revealed significant upregulation of pathways such as RNA polymerase Ⅱ transcription factor binding,negative regulation of DNA binding,and heat shock factor 1-dependent transcriptional activation(P＜0.05).Growth plate chondrocytes in Col10a1-Cre;R26DTA/+mice were in a stress state.Conclusion Induction of abnormal cartilage-to-bone transition in mice with DTA leads to abnormal cartilage matrix accumulation in the growth plate,decrease of osteoclasts,and cellular stress responses in growth plate chondrocytes,which may be the cause of abnormal expansion of the growth plate.
Keywords：hypertrophic chondrocytesendochondral ossificationdiphtheria toxingrowth plategenetically modified mouse modelosteoclaststranscriptome sequencingcellular stress
Publication Date：2025-08-31
Online Publishing Date：2026-08-26(First online date of this platform, not the publication date of the document)
Pages：8( 986-993 )