Related Experiment Video
Updated: Jul 15, 2026

Generation of Enterobacter sp. YSU Auxotrophs Using Transposon Mutagenesis
Published on: October 31, 2014
Characterization of the intron in the phage T4 thymidylate synthase gene and evidence for its self-excision from the
Abstract:
The td gene contains a 735 bp open reading frame within its 1017 bp intron. A 12 nucleotide stretch may form a stable secondary structure with the putative Shine-Dalgarno sequence of the intron open reading frame and thus impair its translation. SP6 RNA polymerase transcripts of the td gene synthesized in vitro at 40 degrees C encompass a 2.7 kb primary transcript, a 1.7 kb mRNA, and a 1 kb intron RNA. The excised intron RNA consisted of linear and cyclized forms. RNAase H studies and resistance of the cyclized intron to linearization by HeLa cell debranching enzyme suggest it to be circular. Self-splicing of isolated td primary transcript occurred only marginally at 28 degrees C, but increased progressively to 50 degrees C, and required the presence of both Mg++ and a guanosine cofactor. An internal guide sequence is evident which may align the 5' splice site with the 3' end, presumably for precise exon ligation.
Related Concept Videos
Eukaryotic Transcription Inhibitors
Eukaryotic transcription inhibitors usually contain two distinct domains, a DNA...
Transcription Attenuation in Prokaryotes
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
Bacterial Transcription
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Restriction Enzymes
The host bacteria protect their own genomic DNA from these enzymes by methylating these sites. Some...

