Open Close
Lu, J., Fu, Y., Kumar, S., Shen, Y., Zeng, K., Xu, A., Carthew, R., Wu, C.I. (2008). Adaptive evolution of newly emerged micro-RNA genes in Drosophila.  Mol. Biol. Evol. 25(5): 929--938.
FlyBase ID
Publication Type
Research paper

How often micro-RNA (miRNA) genes emerged and how fast they evolved soon after their emergence are some of the central questions in the evolution of miRNAs. Because most known miRNA genes are ancient and highly conserved, these questions can be best answered by identifying newly emerged miRNA genes. Among the 78 miRNA genes in Drosophila reported before 2007, only 5 are confirmed to be newly emerged in the genus (although many more can be found in the newly reported data set; e.g., Ruby et al. 2007; Stark et al. 2007; Lu et al. 2008). These new miRNA genes have undergone numerous changes, even in the normally invariant mature sequences. Four of them (the miR-310/311/312/313 cluster, denoted miR-310s) were duplicated from other conserved miRNA genes. The fifth one (miR-303) appears to be a very young gene, originating de novo from a non-miRNA sequence recently. We sequenced these 5 miRNA genes and their neighboring regions from a worldwide collection of Drosophila melanogaster lines. The levels of divergence and polymorphism in these miRNA genes, vis-à-vis those of the neighboring DNA sequences, suggest that these 5 genes are evolving adaptively. Furthermore, the polymorphism pattern of miR-310s in D. melanogaster is indicative of hitchhiking under positive selection. Thus, a large number of adaptive changes over a long period of time may be essential for the evolution of newly emerged miRNA genes.

PubMed ID
PubMed Central ID
PMC3707409 (PMC) (EuropePMC)
Associated Information
Associated Files
Other Information
Secondary IDs
    Language of Publication
    Additional Languages of Abstract
    Parent Publication
    Publication Type
    Mol. Biol. Evol.
    Molecular Biology and Evolution
    Publication Year
    0737-4038 1537-1719
    Data From Reference