Structural insights reveal the specific recognition of roX RNA by the dsRNA-binding domains of the RNA helicase MLE and its indispensable role in dosage compensation in Drosophila.
Nucleic Acids Res
; 47(6): 3142-3157, 2019 04 08.
Article
em En
| MEDLINE
| ID: mdl-30649456
ABSTRACT
In Drosophila, dosage compensation globally upregulates the expression of genes located on male single X-chromosome. Maleless (MLE) helicase plays an essential role to incorporate the roX lncRNA into the dosage compensation complex (MSL-DCC), and such function is essentially dependent on its dsRNA-binding domains (dsRBDs). Here, we report a 2.90Å crystal structure of tandem dsRBDs of MLE in complex with a 55mer stem-loop of roX2 (R2H1). MLE dsRBDs bind to R2H1 cooperatively and interact with two successive minor grooves and a major groove of R2H1, respectively. The recognition of R2H1 by MLE dsRBDs involves both shape- and sequence-specificity. Moreover, dsRBD2 displays a stronger RNA affinity than dsRBD1, and mutations of key residues in either MLE dsRBD remarkably reduce their affinities for roX2 both in vitro and in vivo. In Drosophila, the structure-based mle mutations generated using the CRISPR/Cas9 system, are partially male-lethal and indicate the inter-regulation among the components of the MSL-DCC at multiple levels. Hence, our research provides structural insights into the interactions between MLE dsRBDs and R2H1 and facilitates a deeper understanding of the mechanism by which MLE tandem dsRBDs play an indispensable role in specific recognition of roX and the assembly of the MSL-DCC in Drosophila dosage compensation.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fatores de Transcrição
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RNA de Cadeia Dupla
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Proteínas Cromossômicas não Histona
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Mecanismo Genético de Compensação de Dose
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DNA Helicases
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Proteínas de Drosophila
Limite:
Animals
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article