Long non-coding RNA – big in nervous system development
Despite extensive evidence that ncRNAs are involved in CNS development, research has not recorded a systematic analysis of the part they play. Using Drosophila melanogaster, the LNCRNADROCNS project has performed a detailed survey of long ncRNA (lncRNA) expression and localisation during development in the fruit fly CNS. Researchers used the mushroom body (MB), a structure used for memory formation, to build the model system. The researchers developed a protocol to purify a type of MB neuron known as Kenyon cells (KCs). Using KCs from larvae and adult flies, the team subjected poly-adenylated RNAs to deep sequencing using the rest of the neurons in the brain as a control. In collaboration with a lab in Harvard, the results were compared with sequencing data from a different line of flies as well as octopaminergic neurons. Data was analysed by LNCRNADROCNS and labs in Oxford and Edinburgh. Together, they developed a pipeline combining de novo and genome-assisted assemblies, followed by extensive filtering. Research results show significant overlap between project data and data from Harvard, an indication of its robustness. Moreover, to confirm this, the data from the octopaminergic neurons had no significant overlap with the project’s results. From a pool of 200 new intergenic lncRNAs and almost a 1 000 previously identified, the researchers selected a final 44 lncRNAs based on their quantity in MBs or their high levels of transcription. Results of the project suggest that lncRNAs have a dedicated role in CNS development, possibly extending to function. Due to tissue complexity and technical difficulties, more work has to be dedicated to identify the exact function of the transcripts. Future research to achieve this must focus on detection of small numbers of RNA molecules in the Drosophila brain.
Keywords
Long non-coding RNA, CNS, LNCRNADROCNS, mushroom body, Kenyon cell