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Published on: February 11, 2019
Evolution of general transcription factors
1Institute of Cytology and Genetics of Russian Academy of Sciences, Novosibirsk 90, Russia.
Journal of Molecular Evolution
|December 12, 2012
Summary
The GTF2I gene family evolved through duplications in vertebrates, leading to GTF2IRD1, GTF2I, and GTF2IRD2. Diversification occurred via repeat evolution and atypical substitutions, impacting protein structure and function.
Area of Science:
- Genomics
- Evolutionary Biology
- Molecular Biology
Background:
- The GTF2I (or TFII-I) family comprises general transcription factors involved in gene regulation.
- Three key genes, GTF2IRD1, GTF2I, and GTF2IRD2, have been identified and studied.
- Evidence suggests the family evolved through gene duplication events.
Purpose of the Study:
- To investigate the evolutionary history and diversification of the GTF2I gene family.
- To understand the role of gene duplication and repeat evolution in shaping these genes.
- To analyze the impact of sequence variations on protein structure and function.
Main Methods:
- Phylogenetic analysis of gene structures and sequences.
- Comparative genomics to trace duplication events across vertebrate evolution.
- Analysis of conserved repeats and atypical substitutions within gene sequences.
Main Results:
- The GTF2I gene family originated from duplications in early vertebrates, with subsequent gene loss and gain events.
- Gene duplications, particularly in early vertebrates and mammals, shaped the family's expansion.
- Conserved repeats within these genes underwent intragenic modifications, contributing to protein diversification.
- Atypical substitutions, often in secondary structures, influence protein 3D arrangement and are prevalent in early land vertebrates.
Conclusions:
- The GTF2I gene family's evolution is characterized by recurrent duplications and sequence diversification.
- Structural differentiation of conserved repeats, influenced by atypical substitutions, is a key driver of functional divergence.
- These evolutionary mechanisms have shaped the GTF2I family across major vertebrate lineages.
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