METHODS: High-throughput sequencing was used to profile the transcriptome of differentially expressed circRNAs (DEcircRNAs) in rat ovary under continuous light exposure (12 h:12 h light/light cycle, L/L group) and a control cycle (12 h:12 h light/dark cycle, L/D group). Gene ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and circRNAs-microRNAs-messenger RNAs networks were performed to predict the role of DEcircRNAs in biological processes and pathways. A quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) assay was conducted to verify the high-throughput sequencing results and the expression level of circadian rhythm genes.
RESULTS: In total, 305 circRNAs were differentially expressed between the L/L and L/D groups. Among these, 211 circRNAs were up regulated, while 94 were down regulated. Eight candidate circRNAs from 305 DEcircRNAs were verified by qRT-PCR. Further bioinformatics analysis revealed that interactions between DEcircRNAs and a set of microRNAs involved in ovarian dysfunction-related pathways, such as regulation of androgen receptors, gonadotrophin releasing hormone signaling pathway, endocrine resistance, etc. Subsequently, we identified rno_circ:chr2:86868285-86964272 and rno_circ:chr1:62330221-62360073 may participate in the pathophysiology of ovarian dysfunction by constructing circRNAs-microRNAs-messenger RNAs networks. Meanwhile, constant light reduced the expression of circadian rhythm genes CLOCK, BAML1, PER1, and PER2 compared with that of controls. Caspase3 and Bax were up regulated in the L/L group compared with the L/D group, while Bcl-2 was down regulated.
CONCLUSIONS: In summary, the results reveal that the expression profiles and potential functions of DEcircRNAs in rat ovaries may play important roles in continuous light-induced ovarian dysfunction. These findings provide novel clues and molecular targets for studying the mechanisms and clinical therapy of ovarian dysfunction.
方法:高通量测序用于在连续光照下(12h:12h光/光周期,L/L组)和一个对照周期(12h:12h光/暗周期,L/D组)。基因本体论(GO)富集分析,京都基因和基因组百科全书(KEGG)途径分析,和circRNAs-microRNAs-信使RNAs网络被用来预测DEcircRNAs在生物过程和途径中的作用。进行定量实时逆转录聚合酶链反应(qRT-PCR)检测以验证高通量测序结果和昼夜节律基因的表达水平。
结果:总计,305个circRNAs在L/L和L/D组之间差异表达。其中,211个circRNAs被上调,而94人被下调。通过qRT-PCR验证了来自305个DEcircRNA的8个候选circRNA。进一步的生物信息学分析显示,DEcircRNAs与一组参与卵巢功能障碍相关通路的microRNAs之间的相互作用,如调节雄激素受体,促性腺激素释放激素信号通路,内分泌抵抗,等。随后,我们鉴定rno_circ:chr2:86868285-86964272和rno_circ:chr1:62330221-62360073可能通过构建circRNAs-microRNAs-信使RNAs网络参与卵巢功能障碍的病理生理学。同时,持续光照降低了昼夜节律基因CLOCK的表达,BAML1、PER1和PER2与对照组比较。L/L组与L/D组比拟,Caspase3和Bax均上调,而Bcl-2下调。
结论:总之,结果表明,DEcircRNAs在大鼠卵巢中的表达谱和潜在功能可能在持续光诱导的卵巢功能障碍中起重要作用。这些发现为研究卵巢功能障碍的机制和临床治疗提供了新的线索和分子靶点。