lnc94638 is a testis-specific long non-coding RNA involved in spermatozoa formation in Zeugodacus cucurbitae...

Long non-coding RNAs (lncRNAs) generally display tissue-specific distributions, and testis-specific lncRNAs form the highest proportion of lncRNAs in many species. Here, we presented a detailed analysis of testis-specific lncRNAs in the melon fly, Zeugodacus cucurbitae, a highly destructive insect pest of cucurbitaceous and other related crops. Most testis-specific lncRNAs were found to be long intergenic non-coding RNAs (lincRNA). The size distribution of these lncRNAs ranged between 600 and 1000 nucleotides. Testis-specific lncRNAs that harboured one isoform number and two exons were the most abundant. Compared to other male tissues, the testis had more highly expressed lncRNAs. The quantitative real-time polymerase chain reaction results of 10 randomly selected testis-specific lncRNAs showed expression patterns consistent with RNA-seq data. Further analysis of the most highly expressed testis-specific lncRNA, lnc94638, was undertaken. Fluorescent in situ hybridization assays localized lnc94638 to the apical region of the testis that contains mature spermatozoa. RNA interference-mediated knockdown of lnc94638 expression reduced spermatozoa numbers and impaired the fertility of Z. cucurbitae male. This study provides a catalogue of testis-specific lncRNAs, shows that the testis-specific lnc94638 is involved in spermatogenesis and has the potential to be used for treating male sterility.