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The emerging landscape of small nucleolar RNAs in cell biology.

Dupuis-Sandoval F, Poirier M, Scott MS - Wiley Interdiscip Rev RNA (2015)

Bottom Line: As a family, they have been well characterized as playing a central role in ribosome biogenesis, guiding either the sequence-specific chemical modification of pre-rRNA (ribosomal RNA) or its processing.In recent years, thanks in great part to advances in sequencing methodologies, we have seen many examples of the diversity that exists in the snoRNA family on multiple levels.Under the deluge of novel features and functions that have recently come to light, snoRNAs emerge as a central, dynamic, and highly versatile group of small regulatory RNAs.

View Article: PubMed Central - PubMed

Affiliation: Biochemistry Department, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada.

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Features of small nucleolar RNAs (snoRNAs). (a) Box C/D snoRNAs are characterized by the presence of boxes C/C′ and D/D′ sequence motifs, represented in orange and cyan, respectively. Boxes C and D can interact forming noncanonical G–A pairings resulting in a structural motif called a k-turn (highlighted in purple). The k-turn is stabilized by the presence of canonical base pairing in proximity. Guide regions of box C/D snoRNAs, specifying the residue that will be methylated in the target, are found immediately upstream from the boxes D and/or D′ (shown in pink). The modified residue in the target is base paired with the snoRNA residue located exactly five nucleotides upstream from the box D or D′ (indicated by an asterisk).17 (b) Box H/ACA snoRNAs consist of two hairpins separated by a box H sequence motif (shown in purple) and followed by a box ACA found three nucleotides from the 3′ end (shown in red). The guide regions (shown in pink) specifying the residue that will be pseudouridylated (ψ) in the target are found in bulges in the hairpins and the modified residue is located 14–15 residues upstream from the box H or ACA.18
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fig01: Features of small nucleolar RNAs (snoRNAs). (a) Box C/D snoRNAs are characterized by the presence of boxes C/C′ and D/D′ sequence motifs, represented in orange and cyan, respectively. Boxes C and D can interact forming noncanonical G–A pairings resulting in a structural motif called a k-turn (highlighted in purple). The k-turn is stabilized by the presence of canonical base pairing in proximity. Guide regions of box C/D snoRNAs, specifying the residue that will be methylated in the target, are found immediately upstream from the boxes D and/or D′ (shown in pink). The modified residue in the target is base paired with the snoRNA residue located exactly five nucleotides upstream from the box D or D′ (indicated by an asterisk).17 (b) Box H/ACA snoRNAs consist of two hairpins separated by a box H sequence motif (shown in purple) and followed by a box ACA found three nucleotides from the 3′ end (shown in red). The guide regions (shown in pink) specifying the residue that will be pseudouridylated (ψ) in the target are found in bulges in the hairpins and the modified residue is located 14–15 residues upstream from the box H or ACA.18

Mentions: Typical box C/D snoRNAs (Figure 1(a)) are between 60 and 90 nucleotides in length and are characterized by the presence of conserved boxes C (consensus sequence RUGAUGA) and D (consensus sequence CUGA) near their 5′ and 3′ termini, respectively.2,19,20 The boxes C and D align and fold into a kink-turn (k-turn) motif involving noncanonical G–A base pairing resulting in a sharp bend in the axis of the double-stranded RNA molecule.3,21 The box C/D k-turn is essential for biogenesis and proper localization, serving as a binding site for core box C/D snoRNP proteins.3,19,21,22 Additional motifs, the boxes C′ and D′, with the same consensus sequences as the boxes C and D, respectively, but typically less well conserved and often degenerate, are found toward the middle of the molecule2,20 (Figure 1(a)). The guide regions with complementarity to the targets are located immediately upstream from the boxes D′ and/or D, the modified residues always base pairing with the fifth residue upstream from these motifs.3,19,20,17


The emerging landscape of small nucleolar RNAs in cell biology.

Dupuis-Sandoval F, Poirier M, Scott MS - Wiley Interdiscip Rev RNA (2015)

Features of small nucleolar RNAs (snoRNAs). (a) Box C/D snoRNAs are characterized by the presence of boxes C/C′ and D/D′ sequence motifs, represented in orange and cyan, respectively. Boxes C and D can interact forming noncanonical G–A pairings resulting in a structural motif called a k-turn (highlighted in purple). The k-turn is stabilized by the presence of canonical base pairing in proximity. Guide regions of box C/D snoRNAs, specifying the residue that will be methylated in the target, are found immediately upstream from the boxes D and/or D′ (shown in pink). The modified residue in the target is base paired with the snoRNA residue located exactly five nucleotides upstream from the box D or D′ (indicated by an asterisk).17 (b) Box H/ACA snoRNAs consist of two hairpins separated by a box H sequence motif (shown in purple) and followed by a box ACA found three nucleotides from the 3′ end (shown in red). The guide regions (shown in pink) specifying the residue that will be pseudouridylated (ψ) in the target are found in bulges in the hairpins and the modified residue is located 14–15 residues upstream from the box H or ACA.18
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4696412&req=5

fig01: Features of small nucleolar RNAs (snoRNAs). (a) Box C/D snoRNAs are characterized by the presence of boxes C/C′ and D/D′ sequence motifs, represented in orange and cyan, respectively. Boxes C and D can interact forming noncanonical G–A pairings resulting in a structural motif called a k-turn (highlighted in purple). The k-turn is stabilized by the presence of canonical base pairing in proximity. Guide regions of box C/D snoRNAs, specifying the residue that will be methylated in the target, are found immediately upstream from the boxes D and/or D′ (shown in pink). The modified residue in the target is base paired with the snoRNA residue located exactly five nucleotides upstream from the box D or D′ (indicated by an asterisk).17 (b) Box H/ACA snoRNAs consist of two hairpins separated by a box H sequence motif (shown in purple) and followed by a box ACA found three nucleotides from the 3′ end (shown in red). The guide regions (shown in pink) specifying the residue that will be pseudouridylated (ψ) in the target are found in bulges in the hairpins and the modified residue is located 14–15 residues upstream from the box H or ACA.18
Mentions: Typical box C/D snoRNAs (Figure 1(a)) are between 60 and 90 nucleotides in length and are characterized by the presence of conserved boxes C (consensus sequence RUGAUGA) and D (consensus sequence CUGA) near their 5′ and 3′ termini, respectively.2,19,20 The boxes C and D align and fold into a kink-turn (k-turn) motif involving noncanonical G–A base pairing resulting in a sharp bend in the axis of the double-stranded RNA molecule.3,21 The box C/D k-turn is essential for biogenesis and proper localization, serving as a binding site for core box C/D snoRNP proteins.3,19,21,22 Additional motifs, the boxes C′ and D′, with the same consensus sequences as the boxes C and D, respectively, but typically less well conserved and often degenerate, are found toward the middle of the molecule2,20 (Figure 1(a)). The guide regions with complementarity to the targets are located immediately upstream from the boxes D′ and/or D, the modified residues always base pairing with the fifth residue upstream from these motifs.3,19,20,17

Bottom Line: As a family, they have been well characterized as playing a central role in ribosome biogenesis, guiding either the sequence-specific chemical modification of pre-rRNA (ribosomal RNA) or its processing.In recent years, thanks in great part to advances in sequencing methodologies, we have seen many examples of the diversity that exists in the snoRNA family on multiple levels.Under the deluge of novel features and functions that have recently come to light, snoRNAs emerge as a central, dynamic, and highly versatile group of small regulatory RNAs.

View Article: PubMed Central - PubMed

Affiliation: Biochemistry Department, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada.

Show MeSH