Transcriptional and Small RNA Responses of the White Mold Fungus Sclerotinia sclerotiorum to Infection by a Virulence-Attenuating Hypovirus

• Published in: Viruses Vol. 10; no. 12; p. 713
• Main Authors: Lee Marzano, Shin-Yi, Neupane, Achal, Domier, Leslie
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 14-12-2018; MDPI
• Subjects: Animals; Ascomycota - genetics; Ascomycota - virology; Carbohydrates; Fungal Viruses - physiology; Fungi; Gene expression; Genomes; High-Throughput Nucleotide Sequencing; hypovirus; Infections; Kinases; Lipid metabolism; MicroRNAs; MicroRNAs - genetics; Mycelia; Mycelium - genetics; Mycelium - virology; mycovirus; Phylogeny; Proteins; RNA polymerase; RNA, Messenger - genetics; RNA, Small Interfering - genetics; RNA, Small Untranslated - genetics; RNA, Transfer - genetics; Sclerotinia sclerotiorum; small RNA; Transcription; Transcription, Genetic; tRFs; tRNA; Virulence; Viruses; White mold; United States > US; mycovirus; hypovirus; small RNA; tRFs
• ISSN: 1999-4915; 1999-4915
• DOI: 10.3390/v10120713

Mycoviruses belonging to the family
cause persistent infection of many different host fungi. We previously determined that the white mold fungus,
, infected with Sclerotinia sclerotiorum hypovirus 2-L (SsHV2-L) exhibits reduced virulence, delayed/reduced sclerotial formation, and enhanced production of aerial mycelia. To gain better insight into the cellular basis for these changes, we characterized changes in mRNA and small RNA (sRNA) accumulation in
to infection by SsHV2-L. A total of 958 mRNAs and 835 sRNA-producing loci were altered after infection by SsHV2-L, among which >100 mRNAs were predicted to encode proteins involved in the metabolism and trafficking of carbohydrates and lipids. Both
.
endogenous and virus-derived sRNAs were predominantly 22 nt in length suggesting one dicer-like enzyme cleaves both. Novel classes of endogenous small RNAs were predicted, including phasiRNAs and tRNA-derived small RNAs. Moreover,
.
phasiRNAs, which were derived from noncoding RNAs and have the potential to regulate mRNA abundance in trans, showed differential accumulation due to virus infection. tRNA fragments did not accumulate differentially after hypovirus infection. Hence, in-depth analysis showed that infection of
.
by a hypovirulence-inducing hypovirus produced selective, large-scale reprogramming of mRNA and sRNA production.