Functions of double-stranded RNA-binding domains in nucleocytoplasmic transport

Abstract

International audienceThe double-stranded RNA-binding domain (dsRBD) is a small protein domain found in eukaryotic, prokaryotic and viral proteins, whose central property is to bind to double-stranded RNA (dsRNA). Aside from this major function, recent examples of dsRBDs involved in the regulation of the sub-cellular localization of proteins, suggest that the participation of dsRBDs in nucleocytoplasmic trafficking is likely to represent a widespread auxiliary function of this type of RNA-binding domain. Overall, dsRBDs from proteins involved in many different biological processes have been reported to be implicated in nuclear import and export, as well as cytoplasmic, nuclear and nucleolar retention. Interestingly, the function of dsRBDs in nucleocytoplasmic trafficking is often regulated by their dsRNA-binding capacity, which can either enhance or impair the transport from one compartment to another. Here, we present and discuss the emerging function of dsRBDs in nucleocytoplasmic transport

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 inDrosophila

“…Previous studies have shown that dsRBDs are well-characterized domains that bind dsRNA modules (26,39). In Drosophila dosage compensation, the N-terminal dsRBDs of MLE play an essential role in recognizing the natural dsRNA target.…”

Genetic Insight into the Domain Structure and Functions of Dicer-Type Ribonucleases

“…Mammalian Dicers predominantly localize to the cytoplasm to perform pre-miRNA cleavage, but several reports have provided evidence for nuclear function and localization of these proteins [ 126 , 127 ]. The shuttling properties of hDicer has been attributed to the nuclear localization signal (NLS) comprising a cluster of positively charged residues on the surface of the folded dsRBD [ 128 , 129 ]. The dsRBD-dependent import of hDicer is mediated by Importin-β, Importin-7 and Importin-8 [ 128 ].…”

“…Similar to hDicer, the C-terminal dsRBD of the yeast Schizosaccharomyces pombe Dicer is also critical for the nuclear localization of the protein. In contrast to hDicer, S. pombe Dicer localizes predominantly in the nucleus, near the nuclear pore complexes [ 129 ]. It was shown that the dsRBD from S. pombe Dicer has a C-terminal extension composed of an α-helical turn followed by a zinc-coordination motif [ 129 ].…”

“…In contrast to hDicer, S. pombe Dicer localizes predominantly in the nucleus, near the nuclear pore complexes [ 129 ]. It was shown that the dsRBD from S. pombe Dicer has a C-terminal extension composed of an α-helical turn followed by a zinc-coordination motif [ 129 ]. This structure makes a protein–protein interaction surface for a yet unidentified nuclear protein binding that may cause the nuclear retention of the S. pombe Dicer.…”

RNA Interference: A Natural Immune System of Plants to Counteract Biotic Stressors

“…The function of RNase III domain is to cleave dsRNA, leaving the 2 nt overhang at 3′ end of the product [22,23]. The N- or C-termini of dsRBDs participate in the regulation of the protein nucleo-cytoplasmic distribution and also have the capacity to bind to dsRNAs [24,25]. The specific function of each domain varies depending on the Dicer protein.…”