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Abstract：
Fragile X syndrome is a neuro-developmental disease affecting intellectual abilities and social interactions. Drosophila melanogaster represents a consolidated model to study neuronal pathways underlying this syndrome, especially because the model recapitulates complex behavioural phenotypes. Drosophila Fragile X protein, or FMRP, is required for a normal neuronal structure and for correct synaptic differentiation in both the peripheral and central nervous systems, as well as for synaptic connectivity during development of the neuronal circuits. At the molecular level, FMRP has a crucial role in RNA homeostasis, including a role in transposon RNA regulation in the gonads of D. m. Transposons are repetitive sequences regulated at both the transcriptional and post-transcriptional levels to avoid genomic instability. De-regulation of transposons in the brain in response to chromatin relaxation has previously been related to neurodegenerative events in Drosophila models. Here, we demonstrate for the first time that FMRP is required for transposon silencing in larval and adult brains of Drosophila \"loss of function\" dFmr1 mutants. This study highlights that flies kept in isolation, defined as asocial conditions, experience activation of transposable elements. In all, these results suggest a role for transposons in the pathogenesis of certain neurological alterations in Fragile X as well as in abnormal social behaviors.
摘要：
脆性X综合征是一种影响智力和社会交往的神经发育性疾病。果蝇代表了研究这种综合征的神经元通路的综合模型，特别是因为该模型概括了复杂的行为表型。果蝇脆性X蛋白,或FMRP，是正常的神经元结构和周围和中枢神经系统正确的突触分化所必需的，以及神经元回路发育过程中的突触连接。在分子水平上,FMRP在RNA稳态中起着至关重要的作用，包括转座子RNA调节中的作用。转座子是在转录和转录后水平上调节的重复序列,以避免基因组不稳定。在果蝇模型中,响应染色质松弛的脑中转座子的去调节先前与神经变性事件有关。这里,我们首次证明FMRP是果蝇“功能丧失”dFmr1突变体的幼虫和成年大脑中转座子沉默所必需的。这项研究强调苍蝇是孤立的，定义为社会条件，体验转座因子的激活。总之,这些结果表明转座子在脆性X的某些神经系统改变的发病机理以及异常的社会行为中起作用。
