Epigenetic Regulation of ABA-Induced Transcriptional Responses in Maize
Plants are subjected to extreme environmental conditions and must adapt rapidly. The phytohormone abscisic acid (ABA) accumulates during abiotic stress, signaling transcriptional changes that trigger physiological responses. Epigenetic modifications often facilitate transcription, particularly at ge...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Oxford University Press
2020-05-01
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| Series: | G3: Genes, Genomes, Genetics |
| Subjects: | |
| Online Access: | http://g3journal.org/lookup/doi/10.1534/g3.119.400993 |
| _version_ | 1818657811468386304 |
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| author | Stefania Vendramin Ji Huang Peter A. Crisp Thelma F. Madzima Karen M. McGinnis |
| author_facet | Stefania Vendramin Ji Huang Peter A. Crisp Thelma F. Madzima Karen M. McGinnis |
| author_sort | Stefania Vendramin |
| collection | DOAJ |
| description | Plants are subjected to extreme environmental conditions and must adapt rapidly. The phytohormone abscisic acid (ABA) accumulates during abiotic stress, signaling transcriptional changes that trigger physiological responses. Epigenetic modifications often facilitate transcription, particularly at genes exhibiting temporal, tissue-specific and environmentally-induced expression. In maize (Zea mays), MEDIATOR OF PARAMUTATION 1 (MOP1) is required for progression of an RNA-dependent epigenetic pathway that regulates transcriptional silencing of loci genomewide. MOP1 function has been previously correlated with genomic regions adjoining particular types of transposable elements and genic regions, suggesting that this regulatory pathway functions to maintain distinct transcriptional activities within genomic spaces, and that loss of MOP1 may modify the responsiveness of some loci to other regulatory pathways. As critical regulators of gene expression, MOP1 and ABA pathways each regulate specific genes. To determine whether loss of MOP1 impacts ABA-responsive gene expression in maize, mop1-1 and Mop1 homozygous seedlings were subjected to exogenous ABA and RNA-sequencing. A total of 3,242 differentially expressed genes (DEGs) were identified in four pairwise comparisons. Overall, ABA-induced changes in gene expression were enhanced in mop1-1 homozygous plants. The highest number of DEGs were identified in ABA-induced mop1-1 mutants, including many transcription factors; this suggests combinatorial regulatory scenarios including direct and indirect transcriptional responses to genetic disruption (mop1-1) and/or stimulus-induction of a hierarchical, cascading network of responsive genes. Additionally, a modest increase in CHH methylation at putative MOP1-RdDM loci in response to ABA was observed in some genotypes, suggesting that epigenetic variation might influence environmentally-induced transcriptional responses in maize. |
| first_indexed | 2024-12-17T03:47:25Z |
| format | Article |
| id | doaj.art-3a32d7c8101449129731c7b29c5a4bb4 |
| institution | Directory Open Access Journal |
| issn | 2160-1836 |
| language | English |
| last_indexed | 2024-12-17T03:47:25Z |
| publishDate | 2020-05-01 |
| publisher | Oxford University Press |
| record_format | Article |
| series | G3: Genes, Genomes, Genetics |
| spelling | doaj.art-3a32d7c8101449129731c7b29c5a4bb42022-12-21T22:04:51ZengOxford University PressG3: Genes, Genomes, Genetics2160-18362020-05-011051727174310.1534/g3.119.40099327Epigenetic Regulation of ABA-Induced Transcriptional Responses in MaizeStefania VendraminJi HuangPeter A. CrispThelma F. MadzimaKaren M. McGinnisPlants are subjected to extreme environmental conditions and must adapt rapidly. The phytohormone abscisic acid (ABA) accumulates during abiotic stress, signaling transcriptional changes that trigger physiological responses. Epigenetic modifications often facilitate transcription, particularly at genes exhibiting temporal, tissue-specific and environmentally-induced expression. In maize (Zea mays), MEDIATOR OF PARAMUTATION 1 (MOP1) is required for progression of an RNA-dependent epigenetic pathway that regulates transcriptional silencing of loci genomewide. MOP1 function has been previously correlated with genomic regions adjoining particular types of transposable elements and genic regions, suggesting that this regulatory pathway functions to maintain distinct transcriptional activities within genomic spaces, and that loss of MOP1 may modify the responsiveness of some loci to other regulatory pathways. As critical regulators of gene expression, MOP1 and ABA pathways each regulate specific genes. To determine whether loss of MOP1 impacts ABA-responsive gene expression in maize, mop1-1 and Mop1 homozygous seedlings were subjected to exogenous ABA and RNA-sequencing. A total of 3,242 differentially expressed genes (DEGs) were identified in four pairwise comparisons. Overall, ABA-induced changes in gene expression were enhanced in mop1-1 homozygous plants. The highest number of DEGs were identified in ABA-induced mop1-1 mutants, including many transcription factors; this suggests combinatorial regulatory scenarios including direct and indirect transcriptional responses to genetic disruption (mop1-1) and/or stimulus-induction of a hierarchical, cascading network of responsive genes. Additionally, a modest increase in CHH methylation at putative MOP1-RdDM loci in response to ABA was observed in some genotypes, suggesting that epigenetic variation might influence environmentally-induced transcriptional responses in maize.http://g3journal.org/lookup/doi/10.1534/g3.119.400993abscisic acid (aba)mediator of paramutation1 (mop1)zea maysepigeneticssirnas |
| spellingShingle | Stefania Vendramin Ji Huang Peter A. Crisp Thelma F. Madzima Karen M. McGinnis Epigenetic Regulation of ABA-Induced Transcriptional Responses in Maize G3: Genes, Genomes, Genetics abscisic acid (aba) mediator of paramutation1 (mop1) zea mays epigenetics sirnas |
| title | Epigenetic Regulation of ABA-Induced Transcriptional Responses in Maize |
| title_full | Epigenetic Regulation of ABA-Induced Transcriptional Responses in Maize |
| title_fullStr | Epigenetic Regulation of ABA-Induced Transcriptional Responses in Maize |
| title_full_unstemmed | Epigenetic Regulation of ABA-Induced Transcriptional Responses in Maize |
| title_short | Epigenetic Regulation of ABA-Induced Transcriptional Responses in Maize |
| title_sort | epigenetic regulation of aba induced transcriptional responses in maize |
| topic | abscisic acid (aba) mediator of paramutation1 (mop1) zea mays epigenetics sirnas |
| url | http://g3journal.org/lookup/doi/10.1534/g3.119.400993 |
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