miR828 and miR858 regulate homoeologous MYB2 gene functions in Arabidopsis trichome and cotton fibre development

Tetraploid cotton contains two homoeologous genes GhMYB2A and GhMYB2D but their regulation is unclear. Here, GhMYB2D is shown to accumulate to higher levels than GhMYB2A during fibre initiation, and is a target of two microRNAs, generating ta-siRNAs, suggesting a role for microRNAs in the divergence of duplicate genes and fibre trait.