RESUMO
A novel negative-sense single-stranded RNA mycovirus, designated as "Magnaporthe oryzae mymonavirus 1" (MoMNV1), was identified in the rice blast fungus Magnaporthe oryzae isolate NJ39. MoMNV1 has a single genomic RNA segment consisting of 10,515 nucleotides, which contains six open reading frames. The largest open reading frame contains 5837 bases and encodes an RNA replicase. The six open reading frames have no overlap and are arranged linearly on the genome, but the spacing of the genes is small, with a maximum of 315 bases and a minimum of 80 bases. Genome comparison and phylogenetic analysis indicated that MoMNV1 is a new member of the genus Penicillimonavirus of the family Mymonaviridae.
Assuntos
Micovírus , Genoma Viral , Fases de Leitura Aberta , Oryza , Filogenia , Doenças das Plantas , Vírus de RNA , RNA Viral , Vírus de RNA/genética , Vírus de RNA/isolamento & purificação , Vírus de RNA/classificação , Micovírus/genética , Micovírus/isolamento & purificação , Micovírus/classificação , Oryza/microbiologia , Oryza/virologia , Doenças das Plantas/microbiologia , Doenças das Plantas/virologia , RNA Viral/genética , Ascomicetos/virologia , Ascomicetos/genética , Proteínas Virais/genética , Magnaporthe/virologia , Magnaporthe/genéticaRESUMO
Auxin affects many aspects of plant growth and development by regulating the expression of auxin-responsive genes. As one of the three major auxin-responsive families the Gretchen Hagen3 (GH3) gene family maintains hormonal homeostasis by conjugating excess indole-3-acetic acid (IAA), salicylic acid (SA), and jasmonic acid (JA) to amino acids during hormone and stress-related signaling. Although some work has been carried out the functions of wheat GH3 (TaGH3) family genes in response to abiotic stresses (including salt stress and osmotic stress) are largely unknown. Access to the complete wheat genome sequence permits genome-wide studies on TaGH3s. We performed a systematic identification of the TaGH3 gene family at the genome level and detected 36 members on 14 wheat chromosomes. Many of the genes were segmentally duplicated and Ka/Ks and inter-species synthetic analyses indicated that polyploidization was the contributor to the increased number of TaGH3 members. Phylogenetic analyses revealed that TaGH3 proteins could divided into three major categories (TaGH3-I, TaGH3-II, and TaGH3-III). Diversified cis-elements in the promoters of TaGH3 genes were predicted as essential players in regulating TaGH3 expression patterns. Gene structure and motif analyses indicated that most TaGH3 genes have relatively conserved exon/intron arrangements and motif compositions. Analysis of multiple transcriptome data sets indicated that many TaGH3 genes are responsive to biological and abiotic stresses and possibly have important functions in stress response. qRT-PCR analysis revealed that TaGH3s were induced by salt and osmotic stresses. Customized annotation results revealed that TaGH3s were widely involved in phytohormone response, defense, growth and development, and metabolism. Overall, our work provides a comprehensive insight into the TaGH3 family members, and a basis for the further study of their biological functions in wheat.
Assuntos
Regulação da Expressão Gênica de Plantas/genética , Ácidos Indolacéticos/metabolismo , Triticum/genética , Ciclopentanos , Evolução Molecular , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genoma de Planta/genética , Estudo de Associação Genômica Ampla/métodos , Glucuronidase/genética , Glucuronidase/metabolismo , Família Multigênica/genética , Oxilipinas , Filogenia , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Ácido Salicílico , Estresse Fisiológico/genética , Transcriptoma/efeitos dos fármacos , Transcriptoma/genéticaRESUMO
A novel mycovirus with the proposed name "Magnaporthe oryzae narnavirus virus 1" (MoNV1), was described in the rice blast fungus Magnaporthe oryzae. The virus has a single-stranded (+ss) RNA genome of 2452 nucleotides, contains a single open reading frame (ORF) predicted to encode an RNA-dependent RNA polymerase (RDRP), and is closely related to some viruses of the genus Narnavirus, family Narnaviridae, including Aspergillus fumigatus narnavirus 1 (AfNV1), Neofusicoccum parvum narnavirus 2 (NpNV2) and Alternaria tenuissima narnavirus 1 (AtNV2). Genome sequence comparisons and phylogenetic analysis suggested that MoNV1 is a new member of the genus Narnavirus. The RDRPs of MoNV1 and some closely related narnaviruses do not contain a typical metal-binding "GDD" motif and catalytic site. Further studies are needed to investigate the replication mechanism of these viruses.
