Genomic DNA sequence of silkworm cultured cells. Bombyx mori strain:BmN4

PIWI proteins and PIWI-interacting RNAs (piRNAs) play a central role in repressing transposable elements in animal germ cells. It is thought that piRNAs are mainly produced from discrete genomic loci named piRNA clusters, which often contain many dead transposon remnants from past invasions and have heterochromatic features. Silkworm ovary-derived cultured cells called BmN4 is a well-established model for piRNA research. Here, we characterized BmN4 genome sequence with the long-read sequencer MinION to annotate piRNA clusters.