Polymorphism analyses and protein modelling inform on functional specialization of < i > Piwi < /i >  clade genes in the arboviral vector < i > Aedes albopictus < /i >

by Michele Marconcini, Luis Hernandez, Giuseppe Iovino, Vincent Hou é, Federica Valerio, Umberto Palatini, Elisa Pischedda, Jacob E. Crawford, Bradley J. White, Teresa Lin, Rebeca Carballar-Lejarazu, Lino Ometto, Federico Forneris, Anna-Bella Failloux, Mariangela Bonizzoni Current knowledge of the piRNA pathway is based mainly on studies onDrosophila melanogaster where three proteins of the Piwi subclade of the Argonaute family interact with PIWI-interacting RNAs to silence transposable elements in gonadal tissues. In mosquito species that transmit epidemic arboviruses such as dengue and chikungunya viruses,Piwi clade genes underwent expansion, are also expressed in the soma and cross-talk with proteins of recognized antiviral function cannot be excluded for some Piwi proteins. These observations underscore the importance of expanding our knowledge of the piRNA pathway beyond the model organismD.melanogaster. Here we focus on the emerging arboviral vectorAedes albopictus and we couple traditional approaches of expression and adaptive evolution analyses with most current computational predictions of protein structure to study evolutionary divergence among Piwi clade proteins. Superposition of protein homology models indicate possible high structure similarity among all Piwi proteins, with high levels of amino acid conservation in the inner regions devoted to RNA binding. On the contrary, solvent-exposed surfaces showed low conservation, with several sites under positive sele...
Source: PLoS Neglected Tropical Diseases - Category: Tropical Medicine Authors: Source Type: research