PLOS Genetics study maps developmental role of m6A methyltransferase Mettl16 in Drosophila

A study published in PLOS Genetics by Penghui Song, Lijuan Ma, and Dong Yan characterises the function of the RNA methyltransferase Mettl16 in Drosophila melanogaster, adding to the comparative biology of N6-methyladenosine (m6A) RNA modification across model organisms.

m6A is one of the most abundant internal chemical modifications found on messenger RNA and is installed by several methyltransferases, the best characterised of which is METTL3. METTL16 has been studied in mammalian systems and other organisms, but its function in Drosophila had not previously been described. The authors generated Mettl16 mutant flies and report a notably different phenotype from that seen in mammals: Mettl16 mutants are viable, indicating the enzyme is not essential for survival in this organism. However, both male and female mutants are completely sterile, exhibiting severe gametogenesis defects. Mutant germ cells progress through mitotic and meiotic stages but subsequently fail, suggesting a role for Mettl16 in post-meiotic germ cell development. The mutants also display multiple additional developmental and behavioural abnormalities.

The divergence between Drosophila and mammalian Mettl16 phenotypes provides insight into how the functional importance of RNA modification enzymes has shifted across evolution. The work is relevant to researchers studying epitranscriptomics, RNA biology, and reproductive genetics.