研究人員在10月在線出版的《自然—化學(xué)生物學(xué)》期刊上報(bào)告說(shuō),，他們發(fā)明了一種探討蛋白質(zhì)變性的新化學(xué)生物學(xué)工具。這些新發(fā)明將為許多重要的生物化學(xué)信號(hào)的生物學(xué)功能的確定提供一種框架,。
蛋白質(zhì)通常是由特定的氨基酸編碼,，并被送入細(xì)胞中不同的位置。作為選擇,，多種小化學(xué)基團(tuán)可用于蛋白質(zhì)的修飾,，并讓它們?cè)诩?xì)胞內(nèi)移動(dòng)。通過(guò)將一種特別的氨基酸導(dǎo)入細(xì)胞內(nèi)的蛋白質(zhì)鏈中,，看它對(duì)Pho4蛋白質(zhì)的影響,，Peter G. Schultz和同事研究了蛋白質(zhì)變性的過(guò)程。
這種特別的氨基酸很像構(gòu)成蛋白質(zhì)的絲氨酸,，只是它被一個(gè)大基團(tuán)包圍,，但這種大基團(tuán)在光的照射下會(huì)被移走。一旦暴露在光線中,，通過(guò)一種正常的細(xì)胞過(guò)程,，絲氨酸就會(huì)被一個(gè)磷酸基團(tuán)磷酸化或修飾。Schultz和同事發(fā)現(xiàn),，在蛋白質(zhì)序列中,，每5個(gè)絲氨酸中就有1個(gè)在控制蛋白質(zhì)是否出入細(xì)胞核中發(fā)揮著特別重要的作用。這一新技術(shù)為監(jiān)測(cè)磷酸化的功能提供了一種強(qiáng)有力的新方法,。（科學(xué)時(shí)報(bào)）
原始出處:
Nature Chemical Biology
Published online: 28 October 2007 | doi:10.1038/nchembio.2007.44
Control of protein phosphorylation with a genetically encoded photocaged amino acid
Edward A Lemke1,3, Daniel Summerer1,3, Bernhard H Geierstanger2, Scott M Brittain2 & Peter G Schultz1,2
We genetically encoded the photocaged amino acid 4,5-dimethoxy-2-nitrobenzylserine (DMNB-Ser, 1) in Saccharomyces cerevisiae in response to the amber nonsense codon TAG. This amino acid was converted to serine in living cells by irradiation with relatively low-energy blue light and was used to noninvasively photoactivate phosphorylation of the transcription factor Pho4, which controls the cellular response to inorganic phosphate1. When substituted at phosphoserine sites that control nuclear export of Pho4, 1 blocks phosphorylation and subsequent export by the receptor Msn5 (ref. 2). We triggered phosphorylation of individual serine residues with a visible laser pulse and monitored nuclear export of Pho4-GFP fusion constructs in real time. We observed distinct export kinetics for differentially phosphorylated Pho4 mutants, which demonstrates dynamic regulation of Pho4 function. This methodology should also facilitate the analysis of other cellular processes involving free serine residues, including catalysis, biomolecular recognition and ion transport.
Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road SR202, La Jolla, California 92037, USA.
Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121-1125, USA.
These authors contributed equally to this work.
Correspondence to: Peter G Schultz1,2 Email: [email protected]
