The RNA-binding properties and domain of Rice stripe virus nucleocapsid protein

AbstractRice stripe virus (RSV) transmitted by the small brown planthopper causes severe rice yield losses in Asian countries. Although viral nuclear entry promotes viral replication in host cells, whether this phenomenon occurs in vector cells remains unknown. Therefore, in this study, we systematically evaluated the presence and roles of RSV in the nuclei of vector insect cells. We observed that the nucleocapsid protein (NP) and viral genomic RNAs were partially transported into vector cell nuclei by utilizing the importin α nuclear transport system. When blocking NP nuclear localization, cytoplasmic RSV accumulation significantly increased. In the vector cell nuclei, NP bound the transcription factor YY1 and affected its positive regulation to FAIM. Subsequently, decreased FAIM expression triggered an antiviral caspase-dependent apoptotic reaction. Our results reveal that viral nuclear entry induces completely different immune effects in vector and host cells, providing new insights into the balance between viral load and the immunity pressure in vector insects.

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Characterization and RNA-binding properties of a chloroplast S1-like ribosomal protein.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)41743-7 ◽

1992 ◽

Vol 267 (27) ◽

pp. 19075-19081

Author(s):

B Franzetti ◽

P Carol ◽

R Mache

Keyword(s):

Ribosomal Protein ◽

Rna Binding ◽

Binding Properties

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Trimeric Hantavirus Nucleocapsid Protein Binds Specifically to the Viral RNA Panhandle

Journal of Virology ◽

10.1128/jvi.78.15.8281-8288.2004 ◽

2004 ◽

Vol 78 (15) ◽

pp. 8281-8288 ◽

Cited By ~ 53

Author(s):

M. A. Mir ◽

A. T. Panganiban

Keyword(s):

Nucleocapsid Protein ◽

Rna Binding ◽

Rna Viruses ◽

Sin Nombre Virus ◽

Viral Capsid ◽

Genomic Rna ◽

Rna Molecules ◽

N Protein ◽

High Affinity ◽

Negative Sense

ABSTRACT Hantaviruses are tripartite negative-sense RNA viruses and members of the Bunyaviridae family. The nucleocapsid (N) protein is encoded by the smallest of the three genome segments (S). N protein is the principal structural component of the viral capsid and is central to the hantavirus replication cycle. We examined intermolecular N-protein interaction and RNA binding by using bacterially expressed Sin Nombre virus N protein. N assembles into di- and trimeric forms. The mono- and dimeric forms exist transiently and assemble into a trimeric form. In contrast, the trimer is highly stable and does not efficiently disassemble into the mono- and dimeric forms. The purified N-protein trimer is able to discriminate between viral and nonviral RNA molecules and, interestingly, recognizes and binds with high affinity the panhandle structure composed of the 3′ and 5′ ends of the genomic RNA. In contrast, the mono- and dimeric forms of N bind RNA to form a complex that is semispecific and salt sensitive. We suggest that trimerization of N protein is a molecular switch to generate a protein complex that can discriminate between viral and nonviral RNA molecules during the early steps of the encapsidation process.

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Crystal structure and RNA-binding properties of an Hfq homolog from the deep-branching Aquificae: conservation of the lateral RNA-binding mode

Acta Crystallographica Section D Structural Biology ◽

10.1107/s2059798317000031 ◽

2017 ◽

Vol 73 (4) ◽

pp. 294-315 ◽

Cited By ~ 12

Author(s):

Kimberly A. Stanek ◽

Jennifer Patterson-West ◽

Peter S. Randolph ◽

Cameron Mura

Keyword(s):

Rna Binding ◽

Binding Pocket ◽

Binding Mode ◽

Evolutionary Conservation ◽

Aquifex Aeolicus ◽

Binding Properties ◽

Bacterial Phyla ◽

Mrna Targets ◽

Small Regulatory Rnas ◽

And Function

The host factor Hfq, as the bacterial branch of the Sm family, is an RNA-binding protein involved in the post-transcriptional regulation of mRNA expression and turnover. Hfq facilitates pairing between small regulatory RNAs (sRNAs) and their corresponding mRNA targets by binding both RNAs and bringing them into close proximity. Hfq homologs self-assemble into homo-hexameric rings with at least two distinct surfaces that bind RNA. Recently, another binding site, dubbed the `lateral rim', has been implicated in sRNA·mRNA annealing; the RNA-binding properties of this site appear to be rather subtle, and its degree of evolutionary conservation is unknown. An Hfq homolog has been identified in the phylogenetically deep-branching thermophileAquifex aeolicus(Aae), but little is known about the structure and function of Hfq from basal bacterial lineages such as the Aquificae. Therefore,AaeHfq was cloned, overexpressed, purified, crystallized and biochemically characterized. Structures ofAaeHfq were determined in space groupsP1 andP6, both to 1.5 Å resolution, and nanomolar-scale binding affinities for uridine- and adenosine-rich RNAs were discovered. Co-crystallization with U6RNA reveals that the outer rim of theAaeHfq hexamer features a well defined binding pocket that is selective for uracil. ThisAaeHfq structure, combined with biochemical and biophysical characterization of the homolog, reveals deep evolutionary conservation of the lateral RNA-binding mode, and lays a foundation for further studies of Hfq-associated RNA biology in ancient bacterial phyla.

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