Identification, Characterization and Expression of Methuselah-Like Genes in Dastarcus helophoroides (Coleoptera: Bothrideridae)

Abstract

<i>Dastarcus helophoroides</i>, which has a relatively longer lifespan compared to other insects, is one of the most effective natural enemies of many large-body long-horned beetles. Methuselah (Mth) is associated with the lifespan, stress resistance, and reproduction in <i>Drosophila melanogaster</i>, but Mth is not present in non-drosophiline insects. A number of <i>methuselah-like</i> genes (<i>mth-likes</i>, <i>mthls</i>) have been identified in non-drosophiline insects, but it is still unknown whether they are present in <i>Dastarcus helophoroides</i>. We identified three novel <i>mth-like</i> genes in <i>D. helophoroides</i>: <i>mth-like1</i>, <i>mth-like2</i>, and <i>mth-like5</i>, and carried out bioinformatic analysis based on the full-length nucleic acid sequences and deduced amino acid sequences. Real-time quantitative polymerase chain reaction (RT-qPCR) showed variations in expression patterns of <i>mth-like</i> genes in different tissues (highly expressed in reproductive systems) and at different developmental stages, indicating that <i>mth-likes</i> were likely be involved in reproduction and development. The altered mRNA expression in aging adults and under oxidation, high temperature, and starvation stress, indicated that <i>mth-like</i> genes were likely to be involved in aging and the resistance of oxidation, high temperature, and starvation. These results characterize, for the first time, the basic properties of three <i>mth-like</i> genes from <i>D. helophoroides</i> that probably play important roles in development, aging, reproduction, and stress resistance.