Lozano-Ureña Anna, Montalbán-Loro Raquel, Ferguson-Smith Anne C, Ferrón Sacri R
ERI BiotecMed Departamento de Biología Celular, Universidad de Valencia, Spain.
Department of Genetics, University of Cambridge, Cambridge, UK.
Brain Plast. 2017 Nov 9;3(1):89-98. doi: 10.3233/BPL-160041.
Most genes required for mammalian development are expressed from both maternally and paternally inherited chromosomal homologues. However, there are a small number of genes known as "" that only express a single allele from one parent, which is repressed on the gene from the other parent. Imprinted genes are dependent on epigenetic mechanisms such as DNA methylation and post-translational modifications of the DNA-associated histone proteins to establish and maintain their parental identity. In the brain, multiple transcripts have been identified which show parental origin-specific expression biases. However, the mechanistic relationship with canonical imprinting is unknown. Recent studies on the postnatal neurogenic niches raise many intriguing questions concerning the role of genomic imprinting and gene dosage during postnatal neurogenesis, including how imprinted genes operate in concert with signalling cues to contribute to newborn neurons' formation during adulthood. Here we have gathered the current knowledge on the imprinting process in the neurogenic niches. We also review the phenotypes associated with genetic mutations at particular imprinted in order to consider the impact of imprinted genes in the maintenance and/or differentiation of the neural stem cell pool and during brain tumour formation.
哺乳动物发育所需的大多数基因是从母系和父系遗传的染色体同源物中表达的。然而，有一小部分被称为“印记基因”的基因只从一个亲本表达单个等位基因，而来自另一个亲本的基因则被抑制。印记基因依赖于表观遗传机制，如DNA甲基化和与DNA相关的组蛋白的翻译后修饰，以建立和维持其亲本身份。在大脑中，已鉴定出多种转录本，它们表现出亲本来源特异性的表达偏向。然而，与经典印记的机制关系尚不清楚。最近对出生后神经发生微环境的研究提出了许多有趣的问题，涉及基因组印记和基因剂量在出生后神经发生中的作用，包括印记基因如何与信号线索协同作用，以促进成年期新生神经元的形成。在这里，我们收集了目前关于神经发生微环境中印迹过程的知识。我们还回顾了与特定印记基因的基因突变相关的表型，以便考虑印记基因在神经干细胞池的维持和/或分化以及脑肿瘤形成过程中的影响。
