Gene expression in eukaryotes does not follow a linear process from transcription to translation and mRNA degradation. Instead it follows a circular process in which cytoplasmic mRNA decay crosstalks with nuclear transcription. In many instances, this crosstalk contributes to buffer mRNA at a roughly constant concentration. Whether the mRNA buffering concept operates on the total mRNA concentration or at the gene-specific level, and if the mechanism to do so is a global or a specific one, remain unknown. Here we assessed changes in mRNA concentrations and their synthesis rates along the transcriptome of aneuploid strains of the yeast Saccharomyces cerevisiae. We also assessed mRNA concentrations and their synthesis rates in nonsense-mediated decay (NMD) targets in euploid strains. We found that the altered synthesis rates in the genes from the aneuploid chromosome and the changes in their mRNA stabilities were not counterbalanced. In addition, the stability of NMD targets was not specifically compensated by the changes in synthesis rate. We conclude that there is no genetic compensation of NMD mRNA targets in yeast, and total mRNA buffering uses mostly a global system rather than a gene-specific one.

中文翻译：

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酵母中的总 mRNA 浓度缓冲系统是全局的，而不是基因特异性的

真核生物中的基因表达不遵循从转录到翻译和 mRNA 降解的线性过程。相反，它遵循一个循环过程，其中细胞质 mRNA 衰变与核转录串扰。在许多情况下，这种串扰有助于以大致恒定的浓度缓冲 mRNA。mRNA 缓冲概念是在总 mRNA 浓度上还是在基因特异性水平上起作用，以及这样做的机制是全局的还是特定的，仍然未知。在这里，我们评估了酿酒酵母非整倍体菌株转录组中 mRNA 浓度及其合成速率的变化. 我们还评估了整倍体菌株中无义介导的衰变 (NMD) 靶标中的 mRNA 浓度及其合成率。我们发现，来自非整倍体染色体的基因合成速率的改变和它们的 mRNA 稳定性的变化没有被抵消。此外，合成速率的变化并未特别补偿 NMD 目标的稳定性。我们得出结论，酵母中的 NMD mRNA 靶标没有遗传补偿，总 mRNA 缓冲主要使用全局系统而不是基因特异性系统。