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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Plant Small RNAs: Their Biogenesis, Regulatory Roles, and Functions
Plant cells accumulate small RNA molecules that regulate plant development, genome stability, and environmental responses. These small RNAs fall into three major classes based on their function and mechanisms of biogenesis—microRNAs, heterochromatic small interfering RNAs, and secondary small interfering RNAs—plus several other less well-characterized categories. Biogenesis of each small RNA class requires a pathway of factors, some specific to each pathway and others involved in multiple pathways. Diverse sequenced plant genomes, along with rapid developments in sequencing, imaging, and genetic transformation techniques, have enabled significant progress in understanding the biogenesis, functions, and evolution of plant small RNAs, including those that had been poorly characterized because they were absent or had low representation in Arabidopsis ( Arabidopsis thaliana). Here, we review recent findings about plant small RNAs and discuss our current understanding of their biogenesis mechanisms, targets, modes of action, mobility, and functions in Arabidopsis and other plant species, including economically important crops. Expected final online publication date for the Annual Review of Plant Biology, Volume 74 is May 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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- Award ID(s):
- 1754097
- PAR ID:
- 10404684
- Date Published:
- Journal Name:
- Annual Review of Plant Biology
- Volume:
- 74
- Issue:
- 1
- ISSN:
- 1543-5008
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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