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De novo Identification of Actively Translated Open Reading Frames with Ribosome Profiling Data
Published on: February 18, 2022
Expression of protein-coding genes embedded in ribosomal DNA.
Steinar D Johansen1, Peik Haugen, Henrik Nielsen
1Department of Molecular Biotechnology, Institute of Medical Biology, University of Tromsø, Tromsø, Norway. steinar.johansen@fagmed.uit.no
Biological Chemistry
|June 16, 2007
Summary
Ribosomal DNA (rDNA) contains parasitic elements encoding protein genes. This review explores the expression of these genes, focusing on homing endonuclease genes (HEGs) within group I introns in the nucleolus.
Area of Science:
- Molecular Biology
- Genetics
- Genomics
Background:
- Ribosomal DNA (rDNA) is crucial for ribosomal RNA gene transcription.
- rDNA loci are often interrupted by mobile genetic elements, including introns and retrotransposons.
- Some of these elements encode proteins, such as homing endonuclease genes (HEGs).
Purpose of the Study:
- To review general aspects of protein genes embedded in rDNA.
- To focus on the expression mechanisms of HEGs from group I introns within the nucleolus.
- To highlight recent findings on the role of ribozymes in HEG expression.
Main Methods:
- Literature review of studies on rDNA-embedded protein genes.
- Focus on group I introns and their encoded HEGs.
- Discussion of ribozyme-mediated gene expression mechanisms.
Main Results:
- Protein genes, particularly HEGs, are frequently found within rDNA.
- The expression of most rDNA-embedded genes remains poorly understood.
- Group I and group I-like ribozymes play essential roles in the endogenous expression of HEGs.
Conclusions:
- HEG expression from group I introns in the nucleolus is a complex process.
- Ribozymes are key regulators of HEG expression within rDNA.
- Further research is needed to fully elucidate the expression strategies of these unique genes.
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