RNA

Part:BBa_K5062010

Designed by: Christian Nelson Tejedor Vicera   Group: iGEM24_HKU-HongKong   (2024-09-27)


3' Hepatitis Delta Virus Ribozyme for RNA Release

Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    COMPATIBLE WITH RFC[1000]

Overview

The hepatitis delta virus (HDV) ribozyme is a self-cleaving RNA enzyme that is essential for processing the HDV viral genome during rolling-circle replication.

This can be attached to the 3' of any RNA sequence that requires the sepearation from unnecessary RNA sequences such as resididual terminators, UTRs or polyA tails.

Usage and Biology

The HDV ribozyme has a characteristic nested double-pseudoknot secondary structure with five helical regions (P1, P1.1, P2, P3, P4) (Ferré-D’Amaré & Scott, 2010). The HDV ribozyme catalyzes a site-specific transesterification reaction, where the 2' hydroxyl group of the nucleotide upstream of the cleavage site acts as a nucleophile to attack the adjacent phosphodiester bond. This results in the formation of a 2'-3' cyclic phosphate and a 5' hydroxyl product (Jimenez et al., 2015).

The HDV ribozyme can function through both metal-dependent and metal-independent mechanisms. In the metal-dependent mechanism, a divalent metal ion (typically Mg2+) helps to stabilize the developing negative charge on the 2' nucleophile and the pentavalent phosphorane transition state (Ke et al., 2004). In the metal-independent mechanism, the catalytic cytosine (C75) can act as a general acid to protonate the 5' leaving group (Ferré-D’Amaré & Scott, 2010).

The self-cleavage activity of the HDV ribozyme is essential for processing the HDV genomic and antigenomic RNA strands during rolling-circle replication (Ferré-D'Amaré, A.R et. al,2010). The cleavage generates linear RNA strands with 5' hydroxyl and 2'-3' cyclic phosphate ends, which can then be ligated to form the circular HDV genome (Jimenez, R.M. et al., 2015).

This can be added directly to the 3' end of RNA sequences. Since this is a DNA part, it should be added to the DNA that eventually transcirbes into the relevant RNA sequences.


A diagram depics the design considerations required for using the 3' HDV Ribozyme (UC San Diego, n.d.)


References

Ke, A., Zhou, K., Ding, F., Cate, J. H. D., & Doudna, J. A. (2004). A conformational switch controls hepatitis delta virus ribozyme catalysis. Nature, 429(6988), 201–205. https://doi.org/10.1038/nature02522

Ferré-D’Amaré, A. R., & Scott, W. G. (2010). Small self-cleaving ribozymes. Cold Spring Harbor Perspectives in Biology, 2(10), a003574. https://doi.org/10.1101/cshperspect.a003574

Jimenez, R. M., Polanco, J. A., & Lupták, A. (2015). Chemistry and Biology of Self-Cleaving Ribozymes. Trends in Biochemical Sciences, 40(11), 648–661. https://doi.org/10.1016/j.tibs.2015.09.001

UC San Diego. (n.d.). 3’ Ribozyme design. https://labs.biology.ucsd.edu/zhao/CRISPR_web/3_prime_ribozyme_design.html


[edit]
Categories
Parameters
None