Difference between revisions of "How is msDNA normally produced?"

Revision as of 01:54, 23 April 2009

This page has a lot of very good history about msDNA. [ msDNA History and References]

Here is a 2005 paper on msDNA.

How is msDNA [multicopy single-stranded DNA] normally produced? [Alyndria]

In some strains of E. coli, msDNA linked to RNA is produced by a reverse transcriptase (RT) encoded by a retron.[1] The retron is a genetic substructure containing the gene for reverse transcriptase (RT) as well as the msr-msd region (msr gene codes for msdRNA/ msd gene codes for msDNA) of the transcript, which serves as a template as well as a primer for the RT reaction. Bacterial reverse transcriptases (RTs) are distinctive amongst other RTs in terms of the priming reactions for cDNA (complementary DNA) synthesis. Because the single RNA molecule is used as both template and starting point for DNA replication, the RT forms an unusual 2′,5′-phosphodiester linkage between an internal G residue of the RNA molecule and the 5′ end of the cDNA to initiate cDNA . In this process the bacterial RTs synthesize msDNA. [2] Lampson confirmed that the msDNA contained the DNA-RNA duplex and that the RNA molecule existed as a template for AT in his study of a clinical strain of E. coli (Cl-1).This msDNA formed a secondary hairpin structure, and the RNA portion formed a stem-and loop structure.[3]

(1)Lima 1995 Isolation and Characterization of Host Mutants Defective in msDNA Synthesis: Role of Ribonuclease H in msDNA Synthesis

(2) Lima 1997 A Novel Retron That Produces RNA-less msDNA inEscherichia coliUsing Reverse Transcriptase, (3) REVERSE TRANSCRIPTASE IN E.COLI msDNA