家蚕非编码RNA在神经系统中的表达分析

Expression analysis of non-coding RNAs in the nervous system of the silkworm,Bombyx mori

【目的】非编码RNA(non-coding RNA,ncRNA)在家蚕Bombyx mori发育过程中具有重要调控作用。本研究旨在探索ncRNA参与家蚕神经系统发育的分子机理。【方法】采用实时荧光定量PCR技术对22个中等长度的ncRNA及3个ncRNA的邻近编码基因在家蚕幼虫神经系统中的表达水平进行检测。【结果】8个ncRNA(包括1个C/D box snoRNA,4个H/ACA box snoRNA和3个不能归类的ncRNA)在家蚕5龄幼虫神经组织和非神经组织中均有表达,且在胸腹神经中的表达量明显高于头部神经中的表达量。其中,snoRNA Bm-51,Bm-18和Bm-86在胸腹神经中的表达量分别是头部神经中的23,5和4.7倍。进一步研究发现,这3个内含子起源的ncRNA与其宿主基因在家蚕神经系统中的表达趋势一致,宿主基因在胸腹神经中的表达量也明显高于头部神经中的表达量。【结论】本研究筛选到的在家蚕不同神经部位存在差异表达的ncRNA,特别是在胸腹神经中高表达的ncRNA可能协同其邻近编码基因,参与家蚕神经发育或神经活动过程。该结果为研究ncRNA参与家蚕神经系统发育提供了分子依据,为从非编码RNA角度探索鳞翅目害虫防治提供了新的思路。

[Aim]A large number of genomic transcripts in both prokaryotes and eukaryotes are nonprotein coding RNAs（ ncRNAs）. Accumulated evidences show that ncRNAs play important roles during the development of the silkworm,Bombyx mori. This study aims to explore the molecular mechanisms of ncRNAs in the nervous development of the silkworm. [Methods]Real-time PCR was used to study the expression of 22 ncRNAs and three neighboring genes of ncRNAs in the nervous system of the silkworm.[Results ] Eight ncRNAs including a C /D box snoRNA, four H/ACA box snoRNAs and three unclassified ncRNAs were accumulated much more in the ventral thoracic nerves than in the nerves of head in the 5th instar larvae of the silkworm. Especially,the expression levels of snoRNA Bm-51,Bm-18 and Bm-86 in the ventral thoracic nerves were 23,5 and 4. 7 times as high as those in the nerves of head,respectively. Further studies showed that the expression of host genes was consistent with that of the three intron-origin ncRNAs,with more accumulation in the ventral thoracic nerves than in the nerves of head. [Conclusion]ncRNAs with higher expression in the ventral thoracic nerves might play roles in the activity of nerves through participating in the regulation of their neighboring genes. The results provide a molecular basis for the functional study of ncRNAs in the silkworm,as well as new clues for the lepidopterous pest control.