Abstract

Background

The human pathogen Pneumocystis jirovecii harbors 6 families of major surface glycoproteins (MSGs) encoded by a single gene superfamily. MSGs are presumably responsible for antigenic variation and adhesion to host cells. The genomic organization suggests that a single member of family I is expressed at a given time per cell, whereas members of the other families are simultaneously expressed.

Methods

We analyzed RNA sequences expressed in several clinical samples, using specific weighted profiles for sorting of reads and calling of single-nucleotide variants to estimate the diversity of the expressed genes.

Results

A number of different isoforms of at least 4 MSG families were expressed simultaneously, including isoforms of family I, for which confirmation was obtained in the wet laboratory.

Conclusion

These observations suggest that every single P. jirovecii population is made of individual cells with distinct surface properties. Our results enhance our understanding of the unique antigenic variation system and cell surface structure of P. jirovecii.

中文翻译：

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Pneumocystis jirovecii主要表面糖蛋白超家族在肺炎患者中的表达模式

摘要

背景

人类病原体Pneumocystis jirovecii含有 6 个由单一基因超家族编码的主要表面糖蛋白 (MSG) 家族。MSG 可能负责抗原变异和对宿主细胞的粘附。基因组组织表明家族 I 的单个成员在每个细胞的给定时间表达，而其他家族的成员同时表达。

方法

我们分析了几个临床样本中表达的 RNA 序列，使用特定的加权配置文件对读数进行排序和调用单核苷酸变体来估计表达基因的多样性。

结果

同时表达了至少 4 个 MSG 家族的许多不同同种型，包括家族 I 的同种型，在湿实验室中获得了确认。

结论

这些观察结果表明，每一个P. jirovecii种群都是由具有不同表面特性的单个细胞组成的。我们的结果增强了我们对P. jirovecii独特的抗原变异系统和细胞表面结构的理解。