Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Centre for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
J Proteome Res. 2010 Jan;9(1):341-51. doi: 10.1021/pr900678j.
Hermaphrodites of the nematode Caenorhabditis elegans produce both sperm and oocytes in the same germline. To investigate the process underlying spermatogenesis and oogenesis separately, we used a quantitative proteomics approach applied to two mutant worm lines (fem-3(q20) and fem-1(hc17)) developing only male and female germlines, respectively. We used stable isotopic labeling of whole animals by feeding them either (14)N or (15)N labeled Escherichia coli. This way, we could confidently identify and quantify 1040 proteins in two independent experiments. Of these, approximately 400 proteins showed significant differential expression between female-like and male-like animals. As expected, proteins linked to oogenesis were found to be highly upregulated in the feminized worms, whereas proteins involved in spermatogenesis were found to be highly upregulated in the masculinized worms. This was complemented by many proteins strongly enriched in either mutant. Although the function of the majority of these proteins is unknown, their expression profile indicates that they have an as yet unrecognized role in the development and/or function of the female- and male germline in C. elegans. We show that members of several protein complexes as well as functionally similar proteins show comparable abundance ratios, indicating coregulation of protein expression. Additional analysis comparing our protein data to a previously published microarray data set shows that mRNA and protein expression are poorly correlating. We provide one of the first examples of a large-scale quantitative proteomics experiment in C. elegans and show the potential and feasibility of an approach enabling system-wide accurate quantitative proteomics experiments in this model organism.
秀丽隐杆线虫的雌雄同体在同一生殖系中产生精子和卵子。为了分别研究精子发生和卵子发生的过程，我们使用了一种定量蛋白质组学方法，应用于分别只发育雄性和雌性生殖系的两个突变线虫系（fem-3(q20)和 fem-1(hc17)）。我们通过用（14）N 或（15）N 标记的大肠杆菌喂养整个动物来进行稳定同位素标记。通过这种方式，我们可以在两个独立的实验中自信地鉴定和定量 1040 种蛋白质。其中，大约 400 种蛋白质在雌性样和雄性样动物之间表现出显著的差异表达。正如预期的那样，在雌性化的蠕虫中发现与卵子发生相关的蛋白质高度上调，而在雄性化的蠕虫中发现与精子发生相关的蛋白质高度上调。这一点得到了许多在突变体中强烈富集的蛋白质的补充。尽管这些蛋白质的大多数功能未知，但它们的表达谱表明它们在秀丽隐杆线虫的雌性和雄性生殖系的发育和/或功能中具有尚未被认识的作用。我们表明，几个蛋白质复合物的成员以及功能相似的蛋白质显示出可比的丰度比值，表明蛋白质表达的共调控。将我们的蛋白质数据与之前发表的微阵列数据集进行比较的额外分析表明，mRNA 和蛋白质表达相关性较差。我们提供了秀丽隐杆线虫中第一个大规模定量蛋白质组学实验的实例之一，并展示了在该模式生物中进行系统范围准确定量蛋白质组学实验的潜力和可行性。
