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Nucleotide sequence of mouse L19 ribosomal protein cDNA isolated in screening with tre oncogene probes
T Nakamura1, M Onno, R Mariage-Samson
1Laboratory of Cellular and Molecular Biology, Centre National de la Recherche Scientifique, Villejuif, France.
Abstract:
A cDNA library was prepared from cytoplasmic poly(A)RNA from mouse NIH-3T3 cells carrying a transfected human tre oncogene. Screening with tre gene probes identified a tre cDNA clone 11-4 and a co-purifying weakly hybridizing cDNA clone 11-5. The 11-5-specific RNA was expressed in both nontransfected and tre-transfected NIH-3T3 cells, showing it is of mouse rather than tre gene origin. Its nucleotide sequence was 717 bp long and contained, starting from the first nucleotide, an open reading frame of 588 bp followed by a 3' noncoding region and 26 A residues at the 3' terminus. Comparison with the GenBank data base revealed 93.7% homology with cDNA encoding the rat L19 ribosomal protein. Furthermore, the 196-amino-acid polypeptide deduced from 11-5 was of the same length and contained only one amino acid difference compared with the rat L19 protein. Comparison with the weakly hybridizing tre gene probe showed stretches of homology that were, however, too short to be taken into consideration. We conclude that the 11-5 sequence encodes the mouse L19 ribosomal protein.
Insights
Researchers identified a mouse L19 ribosomal protein gene (11-5) from NIH-3T3 cells. This gene, unrelated to the transfected human tre oncogene, shows high homology to rat L19 ribosomal protein.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- NIH-3T3 cells were transfected with a human tre oncogene.
- A cDNA library was created from cytoplasmic poly(A)RNA of these cells.
- Screening aimed to identify genes related to the tre oncogene.
Purpose of the Study:
- To identify and characterize a novel cDNA clone (11-5) isolated during screening for tre oncogene-related sequences.
- To determine the origin and function of the cDNA clone 11-5.
- To investigate the relationship between clone 11-5 and the transfected tre oncogene.
Main Methods:
- Construction of a cDNA library from mouse NIH-3T3 cells.
- Screening of the cDNA library using tre gene probes.
- Nucleotide sequencing of the identified cDNA clone 11-5.
- Bioinformatic analysis and comparison with existing databases (GenBank).
Main Results:
- A cDNA clone, designated 11-5, was identified alongside a tre cDNA clone (11-4).
- RNA specific to clone 11-5 was expressed in both transfected and non-transfected cells, indicating a mouse origin.
- Sequence analysis revealed 93.7% homology to rat L19 ribosomal protein, with a deduced polypeptide differing by only one amino acid.
Conclusions:
- The cDNA clone 11-5 represents the mouse L19 ribosomal protein.
- The 11-5 sequence is of mouse origin and not derived from the transfected human tre oncogene.
- This finding contributes to the understanding of ribosomal protein gene expression in mammalian cells.