A micro-RNA drives a 100-million-year adaptive evolution of melanic patterns in butterflies and moths

Tian, S.; Banerjee, T. D.; Wee, J. L. Q.; Wang, Y.; Murugesan, S. N.; Monteiro, A.

doi:10.1101/2024.02.09.579741

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bioRxiv · 10.1101/2024.02.09.579741

A micro-RNA drives a 100-million-year adaptive evolution of melanic patterns in butterflies and moths

Tian, S.·Banerjee, T. D.·Wee, J. L. Q.·Wang, Y.·Murugesan, S. N.·Monteiro, A.

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Abstract

In Lepidoptera (butterflies and moths), the genomic region around the gene cortex is a hotspot locus, repeatedly used to generate intraspecific melanic wing color polymorphisms across 100-million-years of evolution. However, the identity of the effector gene regulating melanic wing color within this locus remains unknown. Here, we show that none of the four candidate protein-coding genes within this locus, including cortex, serve as major effectors. Instead, a micro-RNA (miRNA), mir-193, serves as the major effector across three deeply diverged lineages of butterflies, and its function is conserved in Drosophila. In Lepidoptera, mir-193 is derived from a gigantic long non-coding RNA, ivory, and it functions by directly repressing multiple pigmentation genes. We show that a miRNA can drive repeated instances of adaptive evolution in animals.

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Tian, S., Banerjee, T. D., Wee, J. L. Q., Wang, Y., Murugesan, S. N., Monteiro, A.. 2024-02-12. A micro-RNA drives a 100-million-year adaptive evolution of melanic patterns in butterflies and moths. https://doi.org/10.1101/2024.02.09.579741

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