Systematic analysis of long intergenic non-coding RNAs inC. elegansgermline uncovers roles in somatic growth

Long intergenic non-coding RNAs (lincRNAs) are transcripts longer than 200 nucleotides that are transcribed from non-coding loci yet undergo biosynthesis similar to coding mRNAs. The disproportional number of lincRNAs expressed in testes suggests that lincRNAs are important during gametogenesis, but experimental evidence has implicated very few lincRNAs in this process. We took advantage of the relatively limited number of lincRNAs in the genome of the nematodeCaenorhabditis elegansto systematically analyse the functions of lincRNAs during meiosis. We deleted six lincRNA genes that are highly and dynamically expressed in theC. elegansgonad and tested the effects on central meiotic processes. Surprisingly, whereas the lincRNA deletions did not strongly impact fertility, germline apoptosis, crossovers, or synapsis,linc-4was required for somatic growth. Slower growth was observed inlinc-4-deletion mutants and in worms depleted oflinc-4using RNAi, indicating thatlinc-4transcripts are required for this post-embryonic process. Unexpectedly, analysis of worms depleted oflinc-4in soma versus germline showed that the somatic role stems fromlinc-4expression in germline cells. This unique feature suggests that some lincRNAs, like some small non-coding RNAs, are required for germ-soma interactions.

Automated summary

Research has identified the involvement of certain lincRNAs in germ cell division processes in the nematode Caenorhabditis elegans, with linc-4 playing a crucial role in somatic growth. The findings suggest that some lincRNAs may be essential for germ-soma interactions.