Abstract：
Repetitive elements in DNA sequences are a hallmark of Apicomplexan protozoa. A genome-wide screening for Tandem Repeats was conducted in Toxoplasma gondii and related Coccidian parasites with a novel strategy to assess compositional bias. A conserved pattern of GC skew and purine-pyrimidine bias was observed. Compositional bias was also present at the protein level. Glutamic acid was the most abundant amino acid in the purine (GA) rich cluster, while Serine prevailed in pyrimidine (CT) rich cluster. Purine rich repeats, and consequently glutamic acid abundance, correlated with high scores for intrinsically disordered protein regions/domains. Finally, variability was established for repetitive regions within a well-known rhoptry antigen (ROP1) and an uncharacterized hypothetical protein with similar features. The approach we present could be useful to identify potential antigens bearing repetitive elements.
摘要：
DNA序列中的重复元件是顶螺原生动物的标志。在弓形虫和相关球虫寄生虫中对串联重复进行了全基因组筛选，并采用了一种评估成分偏倚的新策略。观察到GC偏斜和嘌呤-嘧啶偏倚的保守模式。在蛋白质水平上也存在成分偏差。谷氨酸是嘌呤(GA)富集簇中含量最丰富的氨基酸,而丝氨酸普遍存在于嘧啶(CT)富集簇。嘌呤丰富的重复，因此谷氨酸丰富，与内在无序的蛋白质区域/结构域的高分相关。最后,在一个众所周知的rhoptry抗原(ROP1)和一个具有相似特征的未表征的假设蛋白内,发现了重复区的变异性.我们提出的方法可用于鉴定带有重复元件的潜在抗原。
