Impact of P-Site tRNA and antibiotics on ribosome mediated protein folding: studies using the Escherichia coli ribosome.
Impact of P-Site tRNA and antibiotics on ribosome mediated protein folding: studies using the Escherichia coli ribosome.
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P位点tRNA和抗生素对核糖体介导的蛋白质折叠的影响：使用大肠杆菌核糖体的研究。
DOI：
10.1371/journal.pone.0101293
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发表时间：
2014
期刊：
影响因子：
3.7
通讯作者：
Barat C
中科院分区：
文献类型：
--
作者：
Mondal S;Pathak BK;Ray S;Barat C
核糖体作为mRNA编码多肽合成的平台，也能够协助多肽链的折叠。催化肽键形成的肽基转移酶中心（PTC）位于细菌核糖体23S rRNA的V结构域。通过与PTC核苷酸的特异性相互作用，正确定位A和p位点trna的3 ' - cca末端对肽基转移酶活性至关重要。这个RNA结构域也是核糖体陪伴活性的中心。未折叠的多肽链与PTC的特定核苷酸相互作用，并以折叠的形式释放。与该结构域相对应的体外转录RNA （bDV RNA）也表现出伴随活性。本研究探讨了trna、A位和p位PTC底物类似物抗生素（purromycin和blasticidin）和大环内酯类抗生素（红霉素和josamycin）对大肠杆菌核糖体和bDV RNA陪伴能力的影响。我们使用mRNA编程核糖体的研究表明，位于p位点的tRNA有效地抑制了核糖体的陪伴功能。我们还发现，与嘌呤霉素或大环内酯类抗生素相比，抗生素blasticidin（模拟P/P位点tRNA的3 ' -CCA端与PTC之间的相互作用）在抑制核糖体和bDV RNA陪伴能力方面更有效。bDV RNA的突变研究可以鉴定核苷酸U2585和G2252（两者都与p位点tRNA相互作用）对其陪伴能力很重要。蛋白质合成及其正确折叠对于维持细胞蛋白质组的功能至关重要。核糖体的PTC具有这两种能力。在p位点结合的tRNA存在时，沉默核糖体的陪伴能力可能是分离这两种重要功能的一种方法。
The ribosome, which acts as a platform for mRNA encoded polypeptide synthesis, is also capable of assisting in folding of polypeptide chains. The peptidyl transferase center (PTC) that catalyzes peptide bond formation resides in the domain V of the 23S rRNA of the bacterial ribosome. Proper positioning of the 3′ –CCA ends of the A- and P-site tRNAs via specific interactions with the nucleotides of the PTC are crucial for peptidyl transferase activity. This RNA domain is also the center for ribosomal chaperoning activity. The unfolded polypeptide chains interact with the specific nucleotides of the PTC and are released in a folding competent form. In vitro transcribed RNA corresponding to this domain (bDV RNA) also displays chaperoning activity. The present study explores the effects of tRNAs, antibiotics that are A- and P-site PTC substrate analogs (puromycin and blasticidin) and macrolide antibiotics (erythromycin and josamycin) on the chaperoning ability of the E. coli ribosome and bDV RNA. Our studies using mRNA programmed ribosomes show that a tRNA positioned at the P-site effectively inhibits the ribosome's chaperoning function. We also show that the antibiotic blasticidin (that mimics the interaction between 3′–CCA end of P/P-site tRNA with the PTC) is more effective in inhibiting ribosome and bDV RNA chaperoning ability than either puromycin or the macrolide antibiotics. Mutational studies of the bDV RNA could identify the nucleotides U2585 and G2252 (both of which interact with P-site tRNA) to be important for its chaperoning ability. Both protein synthesis and their proper folding are crucial for maintenance of a functional cellular proteome. The PTC of the ribosome is attributed with both these abilities. The silencing of the chaperoning ability of the ribosome in the presence of P-site bound tRNA might be a way to segregate these two important functions.
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影响因子：
2.9
作者：
LILL, R;ROBERTSON, JM;WINTERMEYER, W
通讯作者：
WINTERMEYER, W
影响因子：
14.9
作者：
Chowdhury, S;Pal, S;DasGupta, C
通讯作者：
DasGupta, C
影响因子：
4.8
作者：
Argent, RH;Parrott, AM;Radford, SE
通讯作者：
Radford, SE
影响因子：
64.5
作者：
Brodersen, DE;Clemons, WM;Ramakrishnan, V
通讯作者：
Ramakrishnan, V
Shine-Dalgarno 相互作用可防止 AUG 之后的密码子处掺入非同源氨基酸
DOI：
10.1073/pnas.0801974105
发表时间：
2008-08-05
影响因子：
11.1
作者：
Di Giacco, Viviana;Warquez, Viter;Nierhaus, Knud H.
通讯作者：
Nierhaus, Knud H.