Open Access
microRNAs as Master Regulators of the Plant NB-LRR Defense Gene Family via the Production of Phased, Trans-acting siRNAs
Reads0
Chats0
TLDR
In this paper, a search for phased siRNAs (phasiRNAs) found at least 114 Medicago loci, the majority of which were defense-related NB-LRR-encoding genes.Abstract:
Legumes and many nonleguminous plants enter symbiotic interactions with microbes, and it is poorly understood how host plants respond to promote beneficial, symbiotic microbial interactions while suppressing those that are deleterious or pathogenic. Trans-acting siRNAs (tasiRNAs) negatively regulate target transcripts and are characterized by siRNAs spaced in 21-nucleotide (nt) "phased" intervals, a pattern formed by DICER-LIKE 4 (DCL4) processing. A search for phased siRNAs (phasiRNAs) found at least 114 Medicago loci, the majority of which were defense-related NB-LRR-encoding genes. We identified three highly abundant 22-nt microRNA (miRNA) families that target conserved domains in these NB-LRRs and trigger the production of trans-acting siRNAs. High levels of small RNAs were matched to >60% of all ∼540 encoded Medicago NB-LRRs; in the potato, a model for mycorrhizal interactions, phasiRNAs were also produced from NB-LRRs. DCL2 and SGS3 transcripts were also cleaved by these 22-nt miRNAs, generating phasiRNAs, suggesting synchronization between silencing and pathogen defense pathways. In addition, a new example of apparent "two-hit" phasiRNA processing was identified. Our data reveal complex tasiRNA-based regulation of NB-LRRs that potentially evolved to facilitate symbiotic interactions and demonstrate miRNAs as master regulators of a large gene family via the targeting of highly conserved, protein-coding motifs, a new paradigm for miRNA function.read more
Citations
More filters
Journal ArticleDOI
Classification and Comparison of Small RNAs from Plants
TL;DR: Comparisons between the different classes of plant small RNAs help to illuminate key goals for future research.
Journal ArticleDOI
The expanding world of small RNAs in plants
TL;DR: The biogenesis of plant small RNAs, such as microRNAs, secondary siRNAs and heterochromatic siRNas, and their diverse cellular and developmental functions, including in reproductive transitions, genomic imprinting and paramutation are discussed.
Journal ArticleDOI
The Amborella Genome and the Evolution of Flowering Plants
TL;DR: Genome structure and phylogenomic analyses indicate that the ancestral Angiosperm was a polyploid with a large constellation of both novel and ancient genes that survived to play key roles in angiosperm biology.
Journal ArticleDOI
A MicroRNA Superfamily Regulates Nucleotide Binding Site–Leucine-Rich Repeats and Other mRNAs
Padubidri V. Shivaprasad,Ho-Ming Chen,Kanu Patel,Donna M. Bond,Bruno Santos,David C. Baulcombe +5 more
TL;DR: ThemiR482-mediated silencing cascade is suppressed in plants infected with viruses or bacteria so that expression of mRNAs with miR482 or secondary siRNA target sequences is increased, allowing pathogen-inducible expression of NBS-LRR proteins and that it contributes to a novel layer of defense against pathogen attack.
Journal ArticleDOI
RNA silencing suppression by plant pathogens: defence, counter-defence and counter-counter-defence
Nathan Pumplin,Olivier Voinnet +1 more
TL;DR: There is increasing evidence that plants have evolved specific defences against RNA-silencing suppression by pathogens, providing yet another illustration of the never-ending molecular arms race between plant pathogens and their hosts.
References
More filters
Journal ArticleDOI
MicroRNAs: Genomics, Biogenesis, Mechanism, and Function
TL;DR: Although they escaped notice until relatively recently, miRNAs comprise one of the more abundant classes of gene regulatory molecules in multicellular organisms and likely influence the output of many protein-coding genes.
Journal ArticleDOI
Versatile and open software for comparing large genomes
Stefan Kurtz,Adam M. Phillippy,Arthur L. Delcher,Michael E. Smoot,Martin Shumway,Corina Antonescu,Steven L. Salzberg +6 more
TL;DR: The newest version of MUMmer easily handles comparisons of large eukaryotic genomes at varying evolutionary distances, as demonstrated by applications to multiple genomes.
Journal ArticleDOI
Genome sequence of the palaeopolyploid soybean
Jeremy Schmutz,Steven B. Cannon,Jessica A. Schlueter,Jessica A. Schlueter,Jianxin Ma,Therese Mitros,William Nelson,David L. Hyten,Qijian Song,Qijian Song,Jay J. Thelen,Jianlin Cheng,Dong Xu,Uffe Hellsten,Gregory D. May,Yeisoo Yu,Tetsuya Sakurai,Taishi Umezawa,Madan K. Bhattacharyya,Devinder Sandhu,Babu Valliyodan,Erika Lindquist,Myron Peto,David Grant,Shengqiang Shu,David Goodstein,Kerrie Barry,Montona Futrell-Griggs,Brian Abernathy,Jianchang Du,Zhixi Tian,Liucun Zhu,Navdeep Gill,Trupti Joshi,Marc Libault,Ananad Sethuraman,Xue-Cheng Zhang,Kazuo Shinozaki,Henry T. Nguyen,Rod A. Wing,Perry B. Cregan,James E. Specht,Jane Grimwood,Daniel S. Rokhsar,Gary Stacey,Randy C. Shoemaker,Scott A. Jackson +46 more
TL;DR: An accurate soybean genome sequence will facilitate the identification of the genetic basis of many soybean traits, and accelerate the creation of improved soybean varieties.
Journal ArticleDOI
MicroRNAs AND THEIR REGULATORY ROLES IN PLANTS
TL;DR: The importance of miRNA-directed gene regulation during plant development is now particularly clear and typically at the cores of gene regulatory networks, targeting genes that are themselves regulators, such as those encoding transcription factors and F-box proteins.
Journal ArticleDOI
microRNA-Directed Phasing during Trans-Acting siRNA Biogenesis in Plants
TL;DR: Data support a model in which miRNA-guided formation of a 5' or 3' terminus within pre-ta-siRNA transcripts, followed by RDR6-dependent formation of dsRNA and Dicer-like processing, yields phased ta-siRNAs that negatively regulate other genes.