NFAT1 protects articular cartilage against osteoarthritic degradation by directly regulating transcription of specific anabolic and catabolic genes

被引：16

作者：

Zhang, M. ^{[1
,2
,3
]}

Lu, Q. ^{[1
,4
]}

Budden, T. ^{[1
,2
]}

Wang, J. ^{[1
,2
,5
]}

机构：

[1] Univ Kansas, Med Ctr, Kansas City, KS 66103 USA

[2] Univ Kansas, Dept Orthoped Surg, Harrington Lab Mol Orthoped, Med Ctr, Kansas City, KS 66103 USA

[3] Univ Kansas, Med Ctr, Dept Med, Div Allergy Clin Immunol & Rheumatol, Kansas City, KS 66103 USA

[4] Univ Kansas, Med Ctr, Harrington Lab Mol Orthoped, Kansas City, KS USA

[5] Univ Kansas, Med Ctr, Dept Biochem & Mol Biol, Kansas City, KS 66103 USA

来源：

BONE & JOINT RESEARCH | 2019年 / 8卷 / 02期

基金：

美国国家卫生研究院;

关键词：

NFAT1; Gene expression; Osteoarthritis; Chromatin immunoprecipitation; Promoter luciferase reporter assay; HYPOXIA-INDUCIBLE FACTOR-1-ALPHA; NF-ATC; EXPRESSION; CHONDROCYTES; DIFFERENTIATION; DEGENERATION; HIF-1-ALPHA; ACTIVATION; PROTEINS; CALCIUM;

D O I：

10.1302/2046-3758.82.BJR-2018-0114.R1

中图分类号：

Q813 [细胞工程];

学科分类号：

摘要：

Objectives Adult mice lacking the transcription factor NFAT1 exhibit osteoarthritis (OA). The precise molecular mechanism for NFAT1 deficiency-induced osteoarthritic cartilage degradation remains to be clarified. This study aimed to investigate if NFAT1 protects articular cartilage (AC) against OA by directly regulating the transcription of specific catabolic and anabolic genes in articular chondrocytes. Methods Through a combined approach of gene expression analysis and web-based searching of NFAT1 binding sequences, 25 candidate target genes that displayed aberrant expression in Nfat1(-/-) AC at the initiation stage of OA, and possessed at least four NFAT1 binding sites in the promoter of each gene, were selected and tested for NFAT1 transcriptional activities by chromatin immunoprecipitation (ChIP) and promoter luciferase reporter assays using chondrocytes isolated from the AC of three- to four-month-old wild-type mice or Nfat1(-/-) mice with early OA phenotype. Results Chromatin immunoprecipitation assays revealed that NFAT1 bound directly to the promoter of 21 of the 25 tested genes encoding cartilage-matrix proteins, growth factors, inflammatory cytokines, matrix-degrading proteinases, and specific transcription factors. Promoter luciferase reporter assays of representative anabolic and catabolic genes demonstrated that NFAT1-DNA binding functionally regulated the luciferase activity of specific target genes in wild-type chondrocytes, but not in Nfat1(-/-) chondrocytes or in wild-type chondrocytes transfected with plasmids containing mutated NFAT1 binding sequences. Conclusion NFAT1 protects AC against degradation by directly regulating the transcription of target genes in articular chondrocytes. NFAT1 deficiency causes defective transcription of specific anabolic and catabolic genes in articular chondrocytes, leading to increased matrix catabolism and osteoarthritic cartilage degradation.

引用

页码：90 / 100

页数：11