HYL1-CLEAVAGE SUBTILASE 1 (HCS1) suppresses miRNA biogenesis in response to light-to-dark transition.
Proc Natl Acad Sci U S A
; 119(6)2022 02 08.
Article
em En
| MEDLINE
| ID: mdl-35121664
ABSTRACT
The core plant microprocessor consists of DICER-LIKE 1 (DCL1), SERRATE (SE), and HYPONASTIC LEAVES 1 (HYL1) and plays a pivotal role in microRNA (miRNA) biogenesis. However, the proteolytic regulation of each component remains elusive. Here, we show that HYL1-CLEAVAGE SUBTILASE 1 (HCS1) is a cytoplasmic protease for HYL1-destabilization. HCS1-excessiveness reduces HYL1 that disrupts miRNA biogenesis, while HCS1-deficiency accumulates HYL1. Consistently, we identified the HYL1K154A mutant that is insensitive to the proteolytic activity of HCS1, confirming the importance of HCS1 in HYL1 proteostasis. Moreover, HCS1-activity is regulated by light/dark transition. Under light, cytoplasmic CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) E3 ligase suppresses HCS1-activity. COP1 sterically inhibits HCS1 by obstructing HYL1 access into the catalytic sites of HCS1. In contrast, darkness unshackles HCS1-activity for HYL1-destabilization due to nuclear COP1 relocation. Overall, the COP1-HYL1-HCS1 network may integrate two essential cellular pathways the miRNA-biogenetic pathway and light signaling pathway.
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Base de dados:
MEDLINE
Assunto principal:
Processamento Pós-Transcricional do RNA
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Arabidopsis
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Proteínas de Arabidopsis
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MicroRNAs
Idioma:
En
Ano de publicação:
2022
Tipo de documento:
Article