Dataset Information

Genome-wide identification of microRNA and siRNA responsive to endophytic beneficial diazotrophic bacteria in maize.

ABSTRACT:

Background

Small RNA (sRNA) has been described as a regulator of gene expression. In order to understand the role of maize sRNA (Zea mays-hybrid UENF 506-8) during association with endophytic nitrogen-fixing bacteria, we analyzed the sRNA regulated by its association with two diazotrophic bacteria, Herbaspirillum seropedicae and Azospirillum brasilense.

Results

Deep sequencing analysis was done with RNA extracted from plants inoculated with H. seropedicae, allowing the identification of miRNA and siRNA. A total of 25 conserved miRNA families and 15 novel miRNAs were identified. A dynamic regulation in response to inoculation was also observed. A hypothetical model involving copper-miRNA is proposed, emphasizing the fact that the up-regulation of miR397, miR398, miR408 and miR528, which is followed by inhibition of their targets, can facilitate association with diazotrophic bacteria. Similar expression patterns were observed in samples inoculated with A. brasilense. Moreover, novel miRNA and siRNA were classified in the Transposable Elements (TE) database, and an enrichment of siRNA aligned with TE was observed in the inoculated samples. In addition, an increase in 24-nt siRNA mapping to genes was observed, which was correlated with an increase in methylation of the coding regions and a subsequent reduction in transcription.

Conclusion

Our results show that maize has RNA-based silencing mechanisms that can trigger specific responses when plants interact with beneficial endophytic diazotrophic bacteria. Our findings suggest important roles for sRNA regulation in maize, and probably in other plants, during association with diazotrophic bacteria, emphasizing the up-regulation of Cu-miRNA.

SUBMITTER: Thiebaut F

PROVIDER: S-EPMC4168055 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature

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Publications

Genome-wide identification of microRNA and siRNA responsive to endophytic beneficial diazotrophic bacteria in maize.

Thiebaut Flávia F Rojas Cristian A CA Grativol Clícia C Motta Mariana Romeiro MR Vieira Tauan T Regulski Michael M Martienssen Robert A RA Farinelli Laurent L Hemerly Adriana S AS Ferreira Paulo C G PC

BMC genomics 20140906

<h4>Background</h4>Small RNA (sRNA) has been described as a regulator of gene expression. In order to understand the role of maize sRNA (Zea mays-hybrid UENF 506-8) during association with endophytic nitrogen-fixing bacteria, we analyzed the sRNA regulated by its association with two diazotrophic bacteria, Herbaspirillum seropedicae and Azospirillum brasilense.<h4>Results</h4>Deep sequencing analysis was done with RNA extracted from plants inoculated with H. seropedicae, allowing the identificat ...[more]

PMID: 25194793

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Dataset Information

Genome-wide identification of microRNA and siRNA responsive to endophytic beneficial diazotrophic bacteria in maize.

Background

Results

Conclusion

Publications

Genome-wide identification of microRNA and siRNA responsive to endophytic beneficial diazotrophic bacteria in maize.

Similar Datasets

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