Key Laboratory for the Genetics of Developmental & Neuropsychiatric Disorders (Ministry of Education), Bio-X Institutes, Shanghai Jiao Tong University, Shanghai, China.
Key Laboratory of Fertility Preservation and Maintenance of Ministry of Education, Ningxia Medical University, Yinchuan, China.
Cell Prolif. 2022 Jul;55(7):e13242. doi: 10.1111/cpr.13242. Epub 2022 May 28.
This study aimed to clarify the regulation and mechanism of meiotic initiation in FGSC development.
FGSCs were induced to differentiate into meiosis in differentiation medium. RNA sequencing was performed to analysis the difference of transcription level. High-through chromosome conformation capture sequencing (Hi-C) was performed to analysis changes of three-dimensional chromatin structure. Chromosome conformation capture further confirmed a spatial chromatin loop. ChIP-qPCR and dual luciferase reporter were used to test the interaction between Stimulated by retinoic acid gene 8 (STRA8) protein and Trip13 promoter.
Compared with FGSCs, the average diameter of STRA8-positive germ cells increased from 13 μm to 16.8 μm. Furthermore, there were 4788 differentially expressed genes between the two cell stages; Meiosis and chromatin structure-associated terms were significantly enriched. Additionally, Hi-C results showed that FGSCs underwent A/B compartment switching (switch rate was 29.81%), the number of topologically associating domains (TADs) increasing, the average size of TADs decreasing, and chromatin loop changes at genome region of Trip13 from undifferentiated stage to meiosis-initiation stage. Furthermore, we validated that Trip13 promoter contacted distal enhancer to form spatial chromatin loop and STRA8 could bind Trip13 promoter to promote gene expression.
FGSCs underwent chromatin structure remodelling from undifferentiated stage to meiosis-initiation stage, which facilitated STRA8 binding to Trip13 promoter and promoting its expression.
本研究旨在阐明 FGSC 发育过程中减数分裂起始的调控机制。
在分化培养基中诱导 FGSC 向减数分裂分化。进行 RNA 测序以分析转录水平的差异。进行高通量染色体构象捕获测序（Hi-C）以分析三维染色质结构的变化。染色体构象捕获进一步证实了空间染色质环。ChIP-qPCR 和双荧光素酶报告基因检测用于测试视黄酸诱导基因 8（STRA8）蛋白与 Trip13 启动子之间的相互作用。
与 FGSC 相比，STRA8 阳性生殖细胞的平均直径从 13μm 增加到 16.8μm。此外，这两个细胞阶段之间有 4788 个差异表达基因；减数分裂和染色质结构相关术语显著富集。此外，Hi-C 结果表明，FGSC 经历了 A/B 区室转换（转换率为 29.81%），拓扑关联域（TAD）数量增加，TAD 的平均大小减小，并且在未分化阶段到减数分裂起始阶段，Trip13 基因组区域的染色质环发生变化。此外，我们验证了 Trip13 启动子与远端增强子接触形成空间染色质环，并且 STRA8 可以结合 Trip13 启动子以促进基因表达。
FGSC 从未分化阶段到减数分裂起始阶段经历了染色质结构重塑，这有利于 STRA8 结合到 Trip13 启动子并促进其表达。
