Despite well established roles of micro
The engineering of
- NSF-PAR ID:
- 10041220
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Biotechnology Journal
- Volume:
- 12
- Issue:
- 10
- ISSN:
- 1860-6768
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary RNA s in plant development, few aspects have been addressed to understand their effects in seeds especially on lipid metabolism. In this study, we showed that overexpressing microRNA 167A (miR167OE ) in camelina (Camelina sativa ) under a seed‐specific promoter changed fatty acid composition and increased seed size. Specifically, the miR167OE seeds had a lower α‐linolenic acid with a concomitantly higher linoleic acid content than the wild‐type. This decreased level of fatty acid desaturation corresponded to a decreased transcriptional expression of the camelina fatty acid desaturase3 (Cs ) in developing seeds. MiR167 targeted the transcription factor auxin response factor (CsFAD 3ARF 8) in camelina, as had been reported previously in Arabidopsis. Chromatin immunoprecipitation experiments combined with transcriptome analysis indicated that CsARF 8 bound to promoters of camelinabZIP 67ABI 3ABI 3‐bZIP 12 pathway regulateCs expression and affect α‐linolenic acid accumulation. In addition, to decipher the miR167A‐CsFAD 3ARF 8 mediated transcriptional cascade forCs suppression, transcriptome analysis was conducted to implicate mechanisms that regulate seed size in camelina. Expression levels of many genes were altered in miR167FAD 3OE , including orthologs that have previously been identified to affect seed size in other plants. Most notably, genes for seed coat development such as suberin and lignin biosynthesis were down‐regulated. This study provides valuable insights into the regulatory mechanism of fatty acid metabolism and seed size determination, and suggests possible approaches to improve these important traits in camelina. -
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