Transcriptome analysis of conditional mutations in the genes encoding six different essential proteins that influence Sen1-dependent termination in Saccharomyces cerevisiae

The information stored in the DNA of a cell’s chromosomes is transmitted to the rest of the cell by transcribing the DNA into RNA copies or “transcripts”. The fidelity of this process, and thus the health of the cell, depends critically on the proper function of proteins that direct transcription. Since hundreds of genes, each specifying a unique RNA transcript, are arranged in tandem along each chromosome, the beginning and end of each gene must be marked in the DNA sequence. Although encoded in DNA, the signal for terminating an RNA transcript is usually recognized in the transcript itself. We examined the genome-wide functional targets of six proteins implicated in transcription termination by identifying transcripts whose structure or abundance is altered by a mutation that compromises the activity of each protein. For a small minority of transcripts, a mutation in any of the six proteins disrupts termination. Much more commonly, a transcript is affected by a mutation in only one or a few of the six proteins, revealing the varying extent to which the proteins cooperate with one another. We discovered affected transcripts that were not known to be controlled by any of the six proteins, including a cohort of genes required for meiosis.储存在细胞染色体脱氧核糖核酸（DNA）中的遗传信息，会通过将DNA转录为核糖核酸（RNA）拷贝或称“转录本（transcripts）”的方式，传递至细胞其他部位。这一过程的保真度，进而细胞的健康状态，极大程度上依赖于介导转录过程的蛋白质的正常功能。由于数百个各编码一种独特RNA转录本的基因沿每条染色体串联排布，因此每个基因的起始与终止位点必须在DNA序列中被标记出来。尽管RNA转录终止信号由DNA编码，但通常会在转录本自身中被识别。我们通过鉴定那些因突变削弱对应蛋白质活性后，结构或丰度发生改变的转录本，分析了六种与转录终止相关蛋白质的全基因组功能靶点。仅在极少数转录本中，六种蛋白质中任意一种发生突变都会破坏其转录终止过程。而在绝大多数转录本中，仅六种蛋白质中的一种或少数几种发生突变时才会影响其转录终止，这揭示了各蛋白质间协作程度的差异。我们还发现了此前未被发现受这六种蛋白质中任意一种调控的受影响转录本，其中包括一组减数分裂所需的基因。