The Biography of Ribonuclease P

1. The Biography of Ribonuclease P Marta Wegorzewska Macromolecules 5.7.09 www.physorg.com/news144947904.html

2. Discovery: pre-tRNA 1971: Precursor t-RNA Sidney Altman www.oisb.ca/.../pic_members_Sidney_Altman.jpg Altman et al., 1971

3. 41 nt at 5’ end Discovery: 3 nt at 3’ end Isolation and purification of pre-tRNA Altman et al., 1971

4. Discovery: -----------------------------------------> RNase P Evans et al., 2006 Nuclear extracts of E.coli --------> Altman et al., 1971

5. Discovery: purification of RNase P 1972: Purifying RNase P Actions of purified RNase P Robertson et al., 1972

6. Discovery: RNase P: RNA-protein mix 1978: Benjamin Stark (graduate student) identified the RNA and protein subunit of E.coli RNase P M2: methylene blue staining for nucleic acid stain C5: Coomassie brilliant blue staining for protein Stark et al., 1978

7. Discovery: RNase P: a ribonuclease and ribozyme 1983: Cecilia Guerrier-Takada 6= E.coli RNA + protein 7= E.coli RNA (M1 RNA) 8= E.coli protein (C5) Pre-tRNA Mature tRNA Guerrier-Takada et al., 1983

8. Conservation: RNA Evans et al., 2006

9. Conservation: Protein Eukarya Archaea Bacteria Hartmann et al., 2003

10. Summary: Bacteria Archaea Eukarya E.coli M1 RNA; type A (ancestral) B. sub type B (Bacillus) RNA- Protein- H. sap. H1 RNA M. the. one RNA subunit H. sap. 10 proteins: hPop1, Rpp29, Rpp21, Rpp30, hPop5, Rpp14, Rpp20, Rpp25, Rpp40, Rpp38 E.coli one protein: C5 B. sub one protein: P protein M. the. 4 proteins: Pop4, Rpr2, Rpp1, Pop5 Hall et al., 2002

11. Function: ribonuclease RNase P functions to remove extraneous 5' sequences from precursor tRNAs to generate mature tRNA Rnase P, Mg2+ www.science.ca/images/altman_rnase.jpg Evans et al., 2006

12. Mechanism of Action: Pre-tRNA binding to S and C domains of RNase P RNA subunit RNase P protein subunit binding to 5’ end of pre-tRNA

13. Function: Human Rnase P: a transcription factor RNase P protein found at 5S rRNA, 7SL RNA and U6 snRNA genes (non-RNase P substrate genes) and tRNA genes (RNase P substrate genes) Jarrous et al., 2007

14. Potential as a tool: potential as a antibacterial, antiviral and anticancer agent Cobaleda et al., 2001 Can we take advantage of the catalytic function of M1RNA to target bacterial, viral, oncogenic mRNAs??

15. Guide sequences (GS): External guide sequences (EGS): exogenous GS recruits endogenous RNase P Internal guide sequences (IGS): GS covalently linked to M1RNA (M1GS) Cobaleda et al., 2001 Requirements: Complementary to target mRNA 3’ sequence for recognition by M1 RNA (EGS)

16. Application: Anti-bacterial potential: Guerrier-Takada et al. 1995 showed specific targeting of EGS to B-galactosidase and alkaline phosphatase encoding genes (expressions were decreased by 50-60% in E.coli) Anti-viral potential: IGS and EGS used to target herpes simplex virus 1 (HSV-1), human immunodeficiency virus (HIV), human influenza virus, human cytomegalovirus and Kaposi's sarcoma-associated herpesvirus Anti-cancer potential: M1GS used for destruction of chimeric mRNAs created by chromosomal translocation (BCR-ABL) Cobaleda et al., 2001

17. Application: Anti-cancer potential: Ba/F3 cells expressing the human BCR-ABLp190 + M1GS against BCR-ABL p190 Cobaledo et al., 2000

18. Application: advantages for basic science research This sounds awesome! Why don’t hear about it as a tool for used in gene knockdown studies? RNA interference Advantages of EGS/M1GS: EGS uses endogenous RNase P (most abundant, stable and efficient enzymes) resulting in irreversible cleavage of target mRNA Highly specific and does not mistarget (RNA i) Little sign of cytotoxicity