Unpaired nucleotides on the stem of microRNA precursor are important for precise cleavage by Dicer-like 1 in Arabidopsis.
Genes Cells
; 27(4): 280-292, 2022 Apr.
Article
em En
| MEDLINE
| ID: mdl-35143697
ABSTRACT
Dicer-like 1 (DCL1) is a core component of the plant microRNA (miRNA) biogenesis machinery. MiRNA is transcribed as a precursor RNA, termed primary miRNA (pri-miRNA), which is cleaved by DCL1 in two steps to generate miRNA/miRNA* duplex. Pri-miRNA is a single-stranded RNA that forms a hairpin structure with a number of unpaired bases, hereafter called mismatches, on its stem. In the present study, by using purified recombinant Arabidopsis DCL1, we presented evidence that mismatches on the stem of pri-miRNA are important for precise DCL1 cleavage. We showed that a mismatch at the loop-distal side of the end of miRNA/miRNA* duplex is important for efficient cleavage of pri-miRNA in vitro, as previously suggested in planta. On the contrary, mismatches distant from the miRNA/miRNA* duplex region are important for determining the cleavage position by DCL1. The purified DCL1 proteins cleaved mutant pri-miRNA variants without such mismatches at a position at which wild-type pri-miRNA variants are not usually cleaved, resulting in an increased accumulation of small RNA different from miRNA. Therefore, our results suggest that, in addition to the distance from the ssRNA-dsRNA junction, mismatches on the stem of pri-miRNA function as a determinant for precise processing of pri-miRNA by DCL1 in plants.
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01-internacional
Base de dados:
MEDLINE
Assunto principal:
Arabidopsis
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Proteínas de Ciclo Celular
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Proteínas de Arabidopsis
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MicroRNAs
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Ribonuclease III
Idioma:
En
Ano de publicação:
2022
Tipo de documento:
Article