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Summary MicroRNAs (miRNAs) are essential regulators of gene expression in metazoans and plants. In plants, most miRNAs are generated from primary miRNA transcripts (pri‐miRNAs), which are processed by the Dicer‐like 1 (DCL1) complex along with accessory proteins.Serrate‐Associated Protein 1 (SEAP1), a conserved splicing‐related protein, has been studied in human and yeast. However, the functions of SEAP1 in plants remain elusive.Lack ofSEAP1results in embryo lethality and knockdown ofSEAP1by an artificial miRNA (amiRSEAP1) causes pleiotropic developmental defects and reduction in miRNA accumulation. SEAP1 associates with the DCL1 complex, and may promote the interaction of the DCL1 complexes with pri‐miRNAs. SEAP1 also enhances pri‐miRNA accumulation, but does not affect pri‐miRNA transcription, suggesting it may indirectly or directly stabilize pri‐miRNAs. In addition, SEAP1 affects the splicing of some pri‐miRNAs and intron retention of messenger RNAs at global levels.Our findings uncover both conserved and novel functions of SEAP1 in plants. Besides the role as a splicing factor, SEPA1 may promote miRNA biogenesis by positively modulating pri‐miRNA splicing, processing and/or stability.
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One locus with two roles: microRNA‐independent functions of microRNA‐host‐gene locus‐encoded long noncoding RNAs
Abstract Long noncoding RNAs (lncRNAs) are RNA transcripts longer than 200 nucleotides that do not code for proteins. LncRNAs play crucial regulatory roles in several biological processes via diverse mechanisms and their aberrant expression is associated with various diseases. LncRNA genes are further subcategorized based on their relative organization in the genome. MicroRNA (miRNA)‐host‐gene‐derived lncRNAs (lnc‐MIRHGs) refer to lncRNAs whose genes also harbor miRNAs. There exists crosstalk between the processing of lnc‐MIRHGs and the biogenesis of the encoded miRNAs. Although the functions of the encoded miRNAs are usually well understood, whether those lnc‐MIRHGs play independent functions are not fully elucidated. Here, we review our current understanding of lnc‐MIRHGs, including their biogenesis, function, and mechanism of action, with a focus on discussing the miRNA‐independent functions of lnc‐MIRHGs, including their involvement in cancer. Our current understanding of lnc‐MIRHGsstrongly indicates that this class of lncRNAs could play important roles in basic cellular events as well as in diseases. This article is categorized under:Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAsRegulatory RNAs/RNAi/Riboswitches > Biogenesis of Effector Small RNAs
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- Award ID(s):
- 1723008
- PAR ID:
- 10453953
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- WIREs RNA
- Volume:
- 12
- Issue:
- 3
- ISSN:
- 1757-7004
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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