細菌mRNA轉錄后的擴散

由于在細菌被膜封閉的腔室中沒有進行區隔，因此難以確定成熟信使RNA（mRNA）是怎樣在細胞內分布的。Llopis等人利用熒光實驗（這種實驗很難做，因為細菌太小）來跟蹤轉錄后mRNA的擴散。他們發現，出人意料的是，新轉錄的mRNA所表現出的擴散很有限。

Eukaryotic cells spatially organize mRNA processes such as translation and mRNA decay. Much less is clear in bacterial cells where the spatial distribution of mature mRNA remains ambiguous. Using a sensitive method based on quantitative fluorescence in situ hybridization, we show here that in Caulobacter crescentus and Escherichia coli, chromosomally expressed mRNAs largely display limited dispersion from their site of transcription during their lifetime. We estimate apparent diffusion coefficients at least two orders of magnitude lower than expected for freely diffusing mRNA, and provide evidence in C. crescentus that this mRNA localization restricts ribosomal mobility. Furthermore, C. crescentus RNase E appears associated with the DNA independently of its mRNA substrates. Collectively, our findings show that bacteria can spatially organize translation and, potentially, mRNA decay by using the chromosome layout as a template.

他們猜測，堆積的染色體材料可能自己充當了一個區隔，來將轉錄與 mRNA降解分開。