Cross-Kingdom Interactions Between Plant and Fungal Viruses.

The large genetic and structural divergences between plants and fungi may hinder the transmission of viruses between these two kingdoms to some extent. However, recent accumulating evidence from virus phylogenetic analyses and the discovery of naturally occurring virus cross-infection suggest the occurrence of past and current transmissions of viruses between plants and plant-associated fungi. Moreover, artificial virus inoculation experiments showed that diverse plant viruses can multiply in fungi and vice versa.

Similar Characteristics of siRNAs of Plant Viruses Which Replicate in Plant and Fungal Hosts.

RNA silencing is a host innate antiviral mechanism which acts via the synthesis of viral-derived small interfering RNAs (vsiRNAs). We have previously reported the infection of phytopathogenic fungi by plant viruses such as cucumber mosaic virus (CMV) and tobacco mosaic virus (TMV). Furthermore, fungal RNA silencing was shown to suppress plant virus accumulation, but the characteristics of plant vsiRNAs associated with the antiviral response in this nonconventional host remain unknown.

Regulation of phenylpropanoid biosynthesis by MdMYB88 and MdMYB124 contributes to pathogen and drought resistance in apple.

MdMYB88 and MdMYB124 have been demonstrated to be responsible for lignin accumulation in apple under drought stress. In this study, using a metabolomic approach, we identified differentially accumulated phenylpropanoid and flavonoid metabolites in transgenic RNAi plants under control and long-term drought stress conditions in apple roots. We confirmed the regulation of phenylalanine by MdMYB88 and MdMYB124 via UPLC-MS in apple roots under both control and drought conditions.

Facilitative and synergistic interactions between fungal and plant viruses.

Plants and fungi are closely associated through parasitic or symbiotic relationships in which bidirectional exchanges of cellular contents occur. Recently, a plant virus was shown to be transmitted from a plant to a fungus, but it is unknown whether fungal viruses can also cross host barriers and spread to plants. In this study, we investigated the infectivity of Cryphonectria hypovirus 1 (CHV1, family ), a capsidless, positive-sense (+), single-stranded RNA (ssRNA) fungal virus in a model plant, CHV1 replicated in mechanically inoculated leaves but did not spread systemically, but coinoculation with an unrelated plant (+)ssRNA virus, tobacco mosaic virus (TMV, family ), or other plant RNA viruses, enabled CHV1 to systemically infect the plant.

Symptomatic plant viroid infections in phytopathogenic fungi.

Viroids are pathogenic agents that have a small, circular noncoding RNA genome. They have been found only in plant species; therefore, their infectivity and pathogenicity in other organisms remain largely unexplored. In this study, we investigate whether plant viroids can replicate and induce symptoms in filamentous fungi.

Identification of a Novel Hypovirulence-Inducing Hypovirus From .

Mycoviruses are wide spread throughout almost all groups of fungi but only a small number of mycoviruses can attenuate the growth and virulence of their fungal hosts. is an ascomycete fungus that causes leaf spot diseases on various crop plants. In this study, we identified a novel ssRNA mycovirus infecting an f.