Mobilization of a retrotransposon in 5-azacytidine-treated fungus Fusarium oxysporum

Abstract

It is well known that DNA methylation is involved in the control of transposable elements in eukaryotic cells. Recent studies indicate that demethylation of DNA in a mutant of Chlamydomonas and Arabidopsis causes transcriptional activation and mobilization of transposons. In this report, transposition of a retrotransposon was investigated in the phytopathogenic fungus Fusarium oxysporum treated with 5-azacytidine (5azaC), a reagent that causes reduction in the DNA methylation level. The results showed elevated transposition frequency in 5azaC-treated isolates when they were incubated for a long time. However, increase of retrotransposon transcripts was not observed, suggesting that the retrotransposon was mobilized by a mechanism other than its transcriptional activation.

Chromosome Evolution in Connection with Repetitive Sequences and Epigenetics in Plants

“…TEs and the derived repetitive DNA sequences are preferred targets of the epigenetic modification [ 98 , 99 ]. The hypomethylation level induced by a demethylation reagent could cause the activation and transposition of TEs in a fungus [ 100 ]. Epigenetic modification affects most aspects of plant growth, development, and reproduction processes [ 101 , 102 , 103 ].…”

Epigenome manipulation as a pathway to new natural product scaffolds and their congeners

“…Most examples have focused on the use of DNMT inhibitors such as 5-azacytidine (1) and 5-aza-2 0 -deoxycytidine (2), which have demonstrated the ability to reduce the DNA-methylation-mediated silencing of hygromycin-resistance genes in Schizophyllum commune 136 and N. crassa 137 and a phleomycin-resistance gene in Phanerochaete chrysosporium. 138 Chemical inhibition of fungal DNMTs has also been shown to impact a variety of developmental and other cellular processes in Candida albicans, 139 Aspergillus spp., [140][141][142] Fusarium oxysporum, 143,144 and N. crassa. [145][146][147] Some of these data support a role for 1 being capable of inducing heritable epigenetic modifications in fungi, resulting in the acquisition of new and mitotically stable phenotypic characteristics.…”

Chapter 10. Epigenetic Approaches to Natural Product Synthesis in Fungi

“…22 Even before they were known as inhibitors of histone and DNA methyltransferases, agents such as trichostatin A (TSA) and 5-azacytidine (5-AC) were initially shown to have a role in fungal development and other processes in several different species of fungi, including C. albicans, Aspergillus spp., F. oxysporum, and N. crassa. 36,[113][114][115][116][117][118][119][120] Their application in development applies to metazoans as well, as many HDAC and DNMT inhibitors were discovered in a screen for anticancer agents, and have since progressed to clinical testing. 20,22 Combinations of nine different HDAC and DNMT inhibitors against twelve different fungi, including A. flavus, A. westerdijkiae, Cladosporium cladosporoides, Clonostachys sp., Diatrype sp., Penicillium chrysogenum, Penicillium citrinum, Rhizopus sp., Verticillium psallotae, and three unknown filamentous fungi resulted in altered metabolite profiles under at least one condition.…”