Genomic Analysis of an Ascomycete Fungus from the Rice Planthopper Reveals How It Adapts to an Endosymbiotic Lifestyle

Abstract

A number of sap-sucking insects harbor endosymbionts, which are thought to play an important role in the development of their hosts. One of the most important rice pests, the brown planthopper (BPH), Nilaparvata lugens (Stål), harbors an obligatory yeast-like symbiont (YLS) that cannot be cultured in vitro. Genomic information on this YLS would be useful to better understand its evolution. In this study, we performed genome sequencing of the YLS using both 454 and Illumina approaches, generating a draft genome that shows a slightly smaller genome size and relatively higher GC content than most ascomycete fungi. A phylogenomic analysis of the YLS supported its close relationship with insect pathogens. We analyzed YLS-specific genes and the categories of genes that are likely to have changed in the YLS during its evolution. The loss of mating type locus demonstrated in the YLS sheds light on the evolution of eukaryotic symbionts. This information about the YLS genome provides a helpful guide for further understanding endosymbiotic associations in hemiptera and the symbiotic replacement of ancient bacteria with a multifunctional YLS seems to have been a successful change.

A robust phylogenomic timetree for biotechnologically and medically important fungi in the genera Aspergillus and Penicillium

“…Finally, our relaxed molecular clock analysis of the Aspergillaceae phylogeny provides a robust and comprehensive time-scale for the evolution of Aspergillaceae and its two large genera, Aspergillus and Penicillium (Figure 5), filling a gap in the literature. Previous molecular clock studies provided estimates for only four internodes, mostly within the genus Aspergillus (Berbee and Taylor 2001;Hedges et al 2006;Vijaykrishna et al 2006;Kensche et al 2008;Sharpton et al 2009;Da Lage et al 2013;Beimforde et al 2014;Fan et al 2015;Gaya et al 2015) and yielded much broader time intervals. For example, the previous estimate for the origin of Aspergillaceae spanned nearly 100 mya (50-146 mya: Berbee and Taylor 2001;Vijaykrishna et al 2006;Sharpton et al 2009) while our dataset and analysis provided a much narrower range of 44.7 mya (mean: 117.4; 95% CI: 141.5 -96.9).…”

An exceptional family: Ophiocordyceps‐allied fungus dominates the microbiome of soft scale insects (Hemiptera: Sternorrhyncha: Coccidae)

“…How the OAF symbiont affects its soft scale insects is currently unknown. The closely related YLS from a planthopper synthesizes sterols and amino acids and also recycles nitrogen (Douglas, 2016;Fan et al, 2015; Vera-Ponce de Le on, Sanchez-Flores, Rosenblueth, & Mart ınez-Romero, 2016). The YLS of the aphid Cerataphis brasiliensis seems to retain a broader metabolic repertoire, including synthesis of essential and nonessential amino acids, lipids and chitin, and nitrogen metabolism (Vogel & Moran, 2013).…”

Virulensi Wereng Batang Cokelat (Nilaparvata lugens Stål) dan Strategi Pengelolaannya

“…Simbiosis ini membantu serangga mendapatkan nutrisi, membantu perkembangan, reproduksi, dan pertahanan terhadap musuh alami (Chen et al 2011;Dong et al 2011;Tang et al 2010). Endosimbion WBC terdiri atas jamur berfilamen atau khamir (yeast-like symbiotes, YLS) yang bersifat obligat dan bakteri obligat maupun fakultatif (Dong et al 2011;Fan et al 2015).…”