Roles of microRNA in plant defense and virus offense interaction

Abstract

MicroRNAs (miRNA) that are around 22 nucleotides long non-protein-coding RNAs, play key regulatory roles in plants. Recent research findings show that miRNAs are involved in plant defense and viral offense systems. Advances in understanding the mechanism of miRNA biogenesis and evolution are useful for elucidating the complicated roles they play in viral infection networks. In this paper a brief summary of evolution of plant antivirus defense is given and the function of miRNAs involved in plant-virus competition is highlighted. It is believed that miRNAs have several advantages over homology-dependent and siRNA-mediated gene silencing when they are applied biotechnologically to promote plant anti-virus defense. miRNA-mediated anti-virus pathway is an ancient mechanism with a promising future. However, using miRNAs as a powerful anti-virus tool will be better realized only if miRNA genomics and functions in plant viral infection are fully understood.

Computational Identification of Conserved microRNAs and Their Targets in Tea (Camellia sinensis)

“…In plants, miRNAs are involved in diverse aspects of plant growth and development such as leaf morphology and polarity, root formation, transition from juvenile to adult vegetative phase and vegetative to flowering phase, flowering time, floral organ identity and reproduction [5,6]. They are also found to be involved in response to pathogen invasion [7], hormone signaling [8,9], environmental stress [10,11] and promotion of anti-viral defence [12].…”

microRNAs and Mechanical Stress

“…Increasing evidence indicates that miRNAs are also involved in plant responses to biotic and abiotic stresses (Sunkar et al 2007;Lu et al 2008c). In galled loblolly pine (Pinus taeda) stems infected with the fungus Cronartium quercuum f. sp.…”

Ancestral RNA: The RNA biology of the eukaryotic ancestor

“…However, this premise is largely based on studies of the well known ncRNAs (e.g., tRNAs, rRNAs, RNaseP RNA). Studies are beginning to emerge on miRNA evolution, [29][30][31][32] where length be transcribed from the var virulence gene family and coated chromatin in a similar way as the animal Xist RNA and the Drosophila rox RNAs. 86 The regulation of the VSP genes involved in antigenic switching in Giardia has also been thought to be epigenetically regulated.…”

“…29 Many new animal miRNAs for example, have been suggested to arise from accumulation of sequence mutations and not from gene or genome duplication. 25,32 Gu et al 29 take a combinatorial approach in that small scale genomic rearrangements and local duplication as well as whole genome duplications contributed to miRNA evolution within vertebrates. However, they make a strong point that deep phylogenetic analysis (even to deep within vertebrates) is difficult due not only to the short sequence lengths, but also to the complex nucleotide substitution patterns enforced by secondary structure constraints.…”