Role of the global transcriptional regulator PrrA in Rhodobacter sphaeroides 2.4.1:: Combined transcriptome and proteome analysis
Role of the global transcriptional regulator PrrA in Rhodobacter sphaeroides 2.4.1:: Combined transcriptome and proteome analysis
复制标题
DOI：
10.1128/jb.00301-08
复制
发表时间：
2008-07-01
影响因子：
3.2
通讯作者：
Kaplan, Samuel
中科院分区：
文献类型：
--
作者：
Eraso, Jesus M.;Roh, Jung Hyeob;Kaplan, Samuel
PrrBA双组分调节系统是类球红细菌2.4.1中的主要全局调节剂。在这里，我们比较了野生型（WT）和突变体PrrA2细胞的转录组和蛋白质组的档案厌氧生长在黑暗中与二甲基亚砜作为电子受体。PrrA2基因组中存在的约25%的基因在转录水平上受PrrA直接或间接调控，相对于WT为两倍或更多。受影响的基因广泛分布于所有COG（邻苯二甲酸组簇）功能类别，PrrA2细胞中先前未被怀疑的“代谢”基因受到影响。PrrA被发现作为转录的激活因子和抑制因子，在PrrA的存在下，更多的基因被抑制（9：5的比例）。通过我们的色谱研究检测到的编码1，536种肽的基因的分析（相当于基因组的36%覆盖率）显示，编码这些蛋白质的基因中约有20%受到PrrA的正调控，而约有32%受到PrrA的负调控，这与全基因组转录组图谱获得的百分比非常一致。此外，WT和PrrA2细胞的转录组和蛋白质组平均参数值的比较显示出良好的定性一致性，表明转录调控与相应的蛋白质丰度相关，尽管不是一一对应的。通过直接测量随机选择的正调控和负调控基因的mRNA来验证微阵列分析。lacZ转录和kan翻译融合使我们能够映射推定的PrrA结合位点，并揭示了潜在的基因靶点的间接调节PrrA。
The PrrBA two-component regulatory system is a major global regulator in Rhodobacter sphaeroides 2.4.1. Here we have compared the transcriptome and proteome profiles of the wild-type (WT) and mutant PrrA2 cells grown anaerobically in the dark with dimethyl sulfoxide as an electron acceptor. Approximately 25% of the genes present in the PrrA2 genome are regulated by PrrA at the transcriptional level, either directly or indirectly, by twofold or more relative to the WT. The genes affected are widespread throughout all COG (cluster of orthologous group) functional categories, with previously unsuspected "metabolic" genes affected in PrrA2 cells. PrrA was found to act as both an activator and a repressor of transcription, with more genes being repressed in the presence of PrrA (9:5 ratio). An analysis of the genes encoding the 1,536 peptides detected through our chromatographic study, which corresponds to 36% coverage of the genome, revealed that approximately 20% of the genes encoding these proteins were positively regulated, whereas approximately 32% were negatively regulated by PrrA, which is in excellent agreement with the percentages obtained for the whole-genome transcriptome profile. In addition, comparison of the transcriptome and proteome mean parameter values for WT and PrrA2 cells showed good qualitative agreement, indicating that transcript regulation paralleled the corresponding protein abundance, although not one for one. The microarray analysis was validated by direct mRNA measurement of randomly selected genes that were both positively and negatively regulated. lacZ transcriptional and kan translational fusions enabled us to map putative PrrA binding sites and revealed potential gene targets for indirect regulation by PrrA.