Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China.
College of Fisheries, Huazhong Agricultural University, Wuhan, China.
Front Endocrinol (Lausanne). 2023 Feb 3;14:1099130. doi: 10.3389/fendo.2023.1099130. eCollection 2023.
Extensive morphological, biochemical, and cellular changes occur during anuran metamorphosis, which is triggered by a single hormone, thyroid hormone (TH). The function of TH is mainly mediated through thyroid receptor (TR) by binding to the specific thyroid response elements (TREs) of direct response genes, in turn regulating the downstream genes in the cascade. The remodeling of dorsal skeletal muscle during anuran metamorphosis provides the perfect model to identify the immediate early and direct response genes that are important during apoptosis, proliferation, and differentiation of the muscle.
In our current study, we performed Illumina sequencing combined with single-molecule real-time (SMRT) sequencing in the dorsal muscle of after TH, cycloheximide (CHX), and TH_CHX treatment.
We first identified 1,245 differentially expressed transcripts (DETs) after TH exposure, many of which were involved in DNA replication, protein processing in the endoplasmic reticulum, cell cycle, apoptosis, p53 signaling pathway, and protein digestion and absorption. In the comparison of the TH group vs. control group and TH_CHX group vs. CHX group overlapping gene, 39 upregulated and 6 downregulated genes were identified as the TH directly induced genes. Further analysis indicated that AGGTCAnnTnAGGTCA is the optimal target sequence of target genes for TR/RXR heterodimers in . Future investigations on the function and regulation of these genes and pathways should help to reveal the mechanisms governing amphibian dorsal muscle remodeling. These full-length and high-quality transcriptomes in this study also provide an important foundation for future studies in M. fissipes metamorphosis.
在由单一激素甲状腺激素（TH）触发的蛙类变态过程中，会发生广泛的形态、生化和细胞变化。TH 的功能主要通过甲状腺受体（TR）与直接反应基因的特定甲状腺反应元件（TRE）结合来介导，进而调节级联反应中的下游基因。在蛙类变态过程中，背侧骨骼肌的重塑为识别在肌肉凋亡、增殖和分化过程中重要的即时早期和直接反应基因提供了完美的模型。
在本研究中，我们在 TH、环己酰亚胺（CHX）和 TH_CHX 处理后的背部肌肉中进行了 Illumina 测序和单分子实时（SMRT）测序。
我们首先鉴定了 1245 个在 TH 暴露后差异表达的转录本（DETs），其中许多参与 DNA 复制、内质网蛋白质加工、细胞周期、凋亡、p53 信号通路和蛋白质消化吸收。在 TH 组与对照组和 TH_CHX 组与 CHX 组重叠基因的比较中，鉴定出 39 个上调和 6 个下调基因作为 TH 直接诱导的基因。进一步分析表明，AGGTCAnnTnAGGTCA 是 TR/RXR 异二聚体在 中的靶基因的最佳靶序列。对这些基因和途径的功能和调控的未来研究应有助于揭示控制两栖类背侧肌肉重塑的机制。本研究中的这些全长和高质量转录组也为未来 M. fissipes 变态研究提供了重要基础。
