The role of microRNAs in activity-dependent cortical plasticity

描述（由申请人提供）：MicroRNAs （miRNAs）是一种小的进化保守的非编码rna，已被证明在大脑发育和突触可塑性中发挥重要作用。脑表达的mirna被预测在转录后水平上调节多种对皮质可塑性重要的基因的表达。剥夺一只或两只眼睛的视觉输入是研究经验依赖的皮层可塑性的经典范例。然而，感觉剥夺对小鼠视觉皮层miRNA表达的影响尚未被研究。本研究的重点是阐明mirna在小鼠视觉皮层黑暗饲养（DR）和单眼剥夺（MD）后突触变化中的作用。具体来说，我们将首先使用微阵列来确定小鼠初级视觉皮层中哪些mirna在黑暗饲养或单眼剥夺后发生了改变。然后，我们将应用锁定核酸原位杂交和qRT-PCR来验证这些经验依赖性mirna的变化，更重要的是确定它们潜在的层流或细胞特异性。随后将利用慢病毒诱导的mirna过表达，这些mirna在小鼠视觉皮层中单眼剥夺或黑暗饲养后会减少。在md相关mirna的体内操作之后，电生理记录和固有信号的光学成像将首先用于研究它们对经验依赖的皮层可塑性的影响。最后，将进行体内双光子成像，以确定MD和DR相关mirna的过表达是否对初级视觉皮层的树突脊柱动力学有影响。本研究将确定小鼠视觉皮层在单眼剥夺或黑暗饲养后发生改变的mirna，并探索它们在经验依赖性突触可塑性中的作用。我的重点是阐明这些新的小的非编码rna的重要性，这些rna已经与哺乳动物皮层突触可塑性的神经精神疾病有关，通过使用视觉皮层发育作为范例。

DESCRIPTION (provided by applicant): MicroRNAs (miRNAs) are small evolutionary conserved non-coding RNAs that have been shown to play an important role in brain development and synaptic plasticity. Brain expressed miRNAs are predicted to regulate at a posttranscriptional level the expression of multiple genes important for cortical plasticity. Deprivation of visual input from one or two eyes is a classical paradigm for studying experience-dependent cortical plasticity. However, the effect of sensory deprivation in miRNA expression in mouse visual cortex has not yet been investigated. This proposal focuses on elucidating the role of miRNAs in synaptic changes following dark rearing (DR) and monocular deprivation (MD) in mouse visual cortex. Specifically, we will first use microarrays to determine which miRNAs are altered in mouse primary visual cortex following dark rearing or monocular deprivation. We will then apply Locked nucleic acid- in situ hybridization and qRT-PCR to verify the changes in these experience-dependent miRNAs and more importantly determine their potential laminar or cellular specificity. Lentiviral induced overexpression of miRNAs that are reduced following monocular deprivation or dark rearing in mouse visual cortex will then be utilized. Following in vivo manipulation of MD-related miRNAs, electrophysiological recordings and optical imaging of intrinsic signals will first be used to study their effect on experience-dependent cortical plasticity. Lastly, in-vivo two-photon imaging will be carried out to determine if overexpression of both MD and DR related miRNAs has an effect in dendritic spine dynamics of primary visual cortex. This proposal will identify miRNAs that are altered in mouse visual cortex following monocular deprivation or dark rearing and explore their role in experience-dependent synaptic plasticity. My focus is to elucidate the importance of these novel small non coding RNAs that have already been linked to neuropsychiatric disease for mammalian cortical synaptic plasticity by using visual cortex development as a paradigm.