Related Experiment Video
Updated: Jul 31, 2026

Using Reverse Genetics to Manipulate the NSs Gene of the Rift Valley Fever Virus MP-12 Strain to Improve Vaccine Safety and Efficacy
Published on: November 1, 2011
Structure of three spliced mRNAs from region E3 of adenovirus type 2
Abstract:
A cDNA library representing early adenovirus type 2 (Ad2) mRNA was constructed. The cDNA copies were inserted into the PstI cleavage site of the pBR322 plasmid, and clones containing sequences from region E3 of the Ad2 genome were identified by colony hybridization. Selected clones were characterized by restriction enzyme cleavage, hybridization, and partial DNA sequence analysis. The precise structure of three spliced mRNAs was established by comparing the results with the DNA sequence of region E3 from Ad2 (Herissé et al., Nucl. Acids Res. 8 (1980) 2173--2191; Herissé and Galibert, Nucl. Acids Res. 9 (1981) 1229--1249). One of the characterized mRNA species encodes the E3/19K glycoprotein, whereas the other two most likely encode the E3/14K protein. The results demonstrate, moreover, that certain splice points which are used to generate the major E3 mRNAs are also used to splice the supplementary leader segments to the fibre mRNA at late times after infection. Two separate poly(A)-addition sites were identified in region E3 by analysis of the cDNA clones; one is preceded by the hexanucleotide sequence AAUAAA, whereas the other is preceded by an altered hexanucleotide, having the sequence AUUAAA.
Related Concept Videos
RNA Splicing
pre-mRNA Processing
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl guanosine). This 5’ cap helps the...
RNA Splicing
Alternative RNA Splicing
There are five types of alternative RNA splicing that vary in the ways the pre-mRNA segments are removed or retained in the mature mRNA. The first...
Leaky Scanning
Pre-mRNA Processing: Modification of pre-mRNA Ends
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a cap to the 5' end of the growing transcript. In this process, a 5' phosphate is replaced by modified guanosine that has a methyl group attached (7-methyl guanosine). This 5' cap helps the cell...

