Internal_loop

Internal loop

Internal-loops (also termed interior loops) in RNA are found where the double stranded RNA separates due to no Watson-Crick-Franklin base pairing between the nucleotides. Internal-loops differ from Stem-loops as they occur in middle of a stretch of double stranded RNA. The non-canonicoal residues result in the double helix becoming distorted due to unwinding, unstacking and kinking.

Internal-loops can be classified as either symmetrical or asymmetrical, with some asymmetrical internal-loops, also known as bulges. Many important structural motifs are composed of internal loops such as the C-loop,[1] the docking-elbow,[2] kink-turns (k-turn),[3][4] the right-angle,[5] the sarcin/ricin loops (also called bulged-G motifs),[6][7][8] the twist-up motif[9] and the UAA/GAN internal loop motif.[10]

See also


References

  1. Lescoute, A; Leontis, NB; Massire, C; Westhof, E (2005). "Recurrent structural RNA motifs, Isostericity Matrices and sequence alignments". Nucleic Acids Research. 33 (8): 2395–409. doi:10.1093/nar/gki535. PMC 1087784. PMID 15860776.
  2. Lehmann, J; Jossinet, F; Gautheret, D (May 1, 2013). "A universal RNA structural motif docking the elbow of tRNA in the ribosome, RNAse P and T-box leaders". Nucleic Acids Research. 41 (10): 5494–502. doi:10.1093/nar/gkt219. PMC 3664808. PMID 23580544.
  3. Schroeder, KT; McPhee, SA; Ouellet, J; Lilley, DM (Aug 2010). "A structural database for k-turn motifs in RNA". RNA. 16 (8): 1463–8. doi:10.1261/rna.2207910. PMC 2905746. PMID 20562215.
  4. Grabow, WW; Zhuang, Z; Swank, ZN; Shea, JE; Jaeger, L (Nov 23, 2012). "The right angle (RA) motif: a prevalent ribosomal RNA structural pattern found in group I introns". Journal of Molecular Biology. 424 (1–2): 54–67. doi:10.1016/j.jmb.2012.09.012. PMC 3488136. PMID 22999957.
  5. Szewczak, AA; Moore, PB (Mar 17, 1995). "The sarcin/ricin loop, a modular RNA". Journal of Molecular Biology. 247 (1): 81–98. doi:10.1006/jmbi.1994.0124. PMID 7897662.
  6. Leontis, NB; Westhof, E (Oct 30, 1998). "A common motif organizes the structure of multi-helix loops in 16 S and 23 S ribosomal RNAs". Journal of Molecular Biology. 283 (3): 571–83. doi:10.1006/jmbi.1998.2106. PMID 9784367.
  7. Moore PB (1999). "Structural motifs in RNA". Annu. Rev. Biochem. 68: 287–300. doi:10.1146/annurev.biochem.68.1.287. PMID 10872451.
  8. Lee, JC; Gutell, RR; Russell, R (Jul 28, 2006). "The UAA/GAN internal loop motif: a new RNA structural element that forms a cross-strand AAA stack and long-range tertiary interactions". Journal of Molecular Biology. 360 (5): 978–88. doi:10.1016/j.jmb.2006.05.066. PMID 16828489.

Share this article:

This article uses material from the Wikipedia article Internal_loop, and is written by contributors. Text is available under a CC BY-SA 4.0 International License; additional terms may apply. Images, videos and audio are available under their respective licenses.