Group II intron

Group II catalytic intron, D5
full secondary structure of group II intron
Identifiers
SymbolIntron_gpII
RfamRF00029
Other data
PDB structuresPDBe 6cih
Extra informationEntry contains Splicing domain V (D5) and some consensus 3' to it.
Group II catalytic intron, D1-D4
Identifiers
Symbolgroup-II-D1D4
RfamCL00102
Other data
PDB structuresPDBe 4fb0
Extra informationEntry contains D1-D4, parts 5' to D5.

Group II introns are a large class of self-catalytic ribozymes and mobile genetic elements found within the genes of all three domains of life. Ribozyme activity (e.g., self-splicing) can occur under high-salt conditions in vitro. However, assistance from proteins is required for in vivo splicing.[1] In contrast to group I introns, intron excision occurs in the absence of GTP and involves the formation of a lariat, with an A-residue branchpoint strongly resembling that found in lariats formed during splicing of nuclear pre-mRNA. It is hypothesized that pre-mRNA splicing (see spliceosome) may have evolved from group II introns, due to the similar catalytic mechanism as well as the structural similarity of the Group II Domain V substructure to the U6/U2 extended snRNA.[2][3] Finally, their ability to site-specifically insert into DNA sites has been exploited as a tool for biotechnology.[4] For example, group II introns can be modified to make site-specific genome insertions and deliver cargo DNA such as reporter genes or lox sites [5]

  1. ^ Lambowitz AM, Zimmerly S (August 2011). "Group II introns: mobile ribozymes that invade DNA". Cold Spring Harbor Perspectives in Biology. 3 (8): a003616. doi:10.1101/cshperspect.a003616. PMC 3140690. PMID 20463000.
  2. ^ Seetharaman M, Eldho NV, Padgett RA, Dayie KT (February 2006). "Structure of a self-splicing group II intron catalytic effector domain 5: parallels with spliceosomal U6 RNA". RNA. 12 (2): 235–47. doi:10.1261/rna.2237806. PMC 1370903. PMID 16428604.
  3. ^ Valadkhan S (May–Jun 2010). "Role of the snRNAs in spliceosomal active site". RNA Biology. 7 (3): 345–53. doi:10.4161/rna.7.3.12089. PMID 20458185.
  4. ^ Karberg M, Guo H, Zhong J, Coon R, Perutka J, Lambowitz AM (December 2001). "Group II introns as controllable gene targeting vectors for genetic manipulation of bacteria". Nat Biotechnol. 19 (12): 1162–7. doi:10.1038/nbt1201-1162. PMID 11731786. S2CID 18669663.
  5. ^ Cerisy T, Rostain W, Chhun A, Boutard M, Salanoubat M, Tolonen AC (December 2019). "A Targetron-Recombinase System for Large-Scale Genome Engineering of Clostridia". mSphere. 4 (6): e00710-19. doi:10.1128/mSphere.00710-19. PMC 6908422. PMID 31826971.