Gene duplication as a major force in evolution

Journal of genetics

Urbi Banerjee¹  Santoshkumar Magadum1³  Rajasekar Ravikesavan²  Doddabhimappa Gangapur²  Priyadharshini Murugan⁴ 

[1] Department of Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University (TNAU), Coimbatore 641 003, India$$;Centre for Plant Breeding and Genetics, Tamil Nadu Agricultural University (TNAU), Coimbatore 641 003, India$$;Department of Genetics and Plant Breeding, G. B. Pant University of Agriculture and Technology, Pantnagar 263 145, India$$;Department of Environmental Sciences, Tamil Nadu Agricultural University (TNAU), Coimbatore 641 003, India$$

关键词: diversity;    duplicated genes;    evolution;    genome duplication;    mutation;    polyploidy.;   

DOI  :  

学科分类：生物科学（综合）

来源: Indian Academy of Sciences

【 摘 要 】

Gene duplication is an important mechanism for acquiring new genes and creating genetic novelty in organisms. Many new gene functions have evolved through gene duplication and it has contributed tremendously to the evolution of developmental programmes in various organisms. Gene duplication can result from unequal crossing over, retroposition or chromosomal (or genome) duplication. Understanding the mechanisms that generate duplicate gene copies and the subsequent dynamics among gene duplicates is vital because these investigations shed light on localized and genomewide aspects of evolutionary forces shaping intra-specific and inter-specific genome contents, evolutionary relationships, and interactions. Based on whole-genome analysis of Arabidopsis thaliana, there is compelling evidence that angiosperms underwent two whole-genome duplication events early during their evolutionary history. Recent studies have shown that these events were crucial for creation of many important developmental and regulatory genes found in extant angiosperm genomes. Recent studies also provide strong indications that even yeast (Saccharomyces cerevisiae), with its compact genome, is in fact an ancient tetraploid. Gene duplication can provide new genetic material for mutation, drift and selection to act upon, the result of which is specialized or new gene functions. Without gene duplication the plasticity of a genome or species in adapting to changing environments would be severely limited. Whether a duplicate is retained depends upon its function, its mode of duplication, (i.e. whether it was duplicated during a whole-genome duplication event), the species in which it occurs, and its expression rate. The exaptation of preexisting secondary functions is an important feature in gene evolution, just as it is in morphological evolution.

【 授权许可】

Unknown