PubReading [330] - Diversity and Complexity of the Large Surface Protein Family in the Compacted Genomes of Multiple Pneumocystis Species - L. Ma, J. Kovacs et al.

<strong>Pneumocystis</strong><em>, </em>a major opportunistic pathogen in patients with a broad range of immunodeficiencies, contains abundant surface proteins encoded by a multicopy gene family, termed the <strong>major surface glycoprotein</strong> (Msg) gene superfamily. This superfamily has been identified in all <em>Pneumocystis </em>species characterized to date, highlighting its important role in <em>Pneumocystis </em>biology. In this report, through a comprehensive and in-depth characterization of 459 <em>msg </em>genes from 7 <em>Pneumocys- tis </em>species, we demonstrate, for the first time, the <strong>phylogeny</strong> and <strong>evolution</strong> of conserved domains in Msg proteins and provide a detailed description of the classification, unique characteristics, and phylogenetic relatedness of five Msg families. We further describe, for the first time, the relative expression levels of individual <em>msg </em>families in two rodent <em>Pneumocystis </em>species, the substantial variability of the <em>msg </em>repertoires in <em>P. carinii </em>from laboratory and wild rats, and the distinct features of the expression site for the classic <em>msg </em>genes in <em>Pneumocystis </em>from 8 mammalian host <strong>species</strong>. Our analysis suggests multiple functions for this superfamily rather than just conferring antigenic variation to allow immune evasion as previously believed. This study provides a rich source of information that lays the foundation for the continued experimental exploration of the functions of the Msg superfamily in <em>Pneumocystis </em>biology.<a href="https://doi.org/10"><em>https://doi.org/10</em></a><em> .1128/mBio.02878-19 - 2020</em>