Brown Christopher J, Kaufman Thomas, Trinidad Jonathan C, Clemmer David E
Department of Chemistry, Indiana University, Bloomington, IN, 47405, United States.
Department of Biology, Indiana University, Bloomington, IN, 47405, United States.
Int J Mass Spectrom. 2018 Feb;425:36-46. doi: 10.1016/j.ijms.2018.01.003. Epub 2018 Jan 10.
A combination of liquid chromatography, ion mobility spectrometry, mass spectrometry, and database searching techniques were used to characterize the proteomes of four biological replicates of adult heads at seven time points across their lifespans. Based on the detection of tryptic peptides, the identities of 1281 proteins were determined. An estimate of the abundance of each protein, based on the three most intense peptide ions, shows that the quantified species vary in concentration over a factor of ~10. Compared to initial studies in the field of Drosophila proteomics, our current results show an eight-fold higher temporal protein coverage with increased quantitative accuracy. Across the lifespan, we observe a range of trends in the abundance of different proteins, including: an increase in abundance of proteins involved in oxidative phosphorylation, and the tricarboxylic acid cycle; a decrease in proteasomal proteins, as well as ribosomal proteins; and, many types of proteins, which remain relatively unchanged. For younger flies, proteomes are relatively similar within their age group. For older flies, proteome similarity decreases within their age group. These combined results illustrate a correlation between increasing age and decreasing proteostasis.
采用液相色谱、离子淌度谱、质谱和数据库搜索技术相结合的方法，对成年果蝇头部在其寿命期间七个时间点的四个生物学重复样本的蛋白质组进行了表征。基于胰蛋白酶肽段的检测，确定了1281种蛋白质的身份。根据三个强度最高的肽离子对每种蛋白质丰度进行估计，结果表明定量的蛋白质种类在浓度上相差约10倍。与果蝇蛋白质组学领域的初步研究相比，我们目前的结果显示，随着定量准确性的提高，时间上的蛋白质覆盖率提高了八倍。在整个寿命期间，我们观察到不同蛋白质丰度呈现出一系列趋势，包括：参与氧化磷酸化和三羧酸循环的蛋白质丰度增加；蛋白酶体蛋白质以及核糖体蛋白质丰度下降；以及许多类型的蛋白质保持相对不变。对于较年轻的果蝇，其蛋白质组在年龄组内相对相似。对于较老的果蝇，其蛋白质组在年龄组内的相似性降低。这些综合结果说明了年龄增长与蛋白质稳态下降之间的相关性。
