Expression profiling analysis of mouse P4 cerebellum in CitK mutant mice proficient or knockout for P53

Purpose: Citron kinase (CitK) knockout mice show a severe form of primary microcephaly, associated with ataxia and lethal epilepsy. This phenotype is caused by massive apoptosis occuring during embryonic and post-natal brain development, associated with cytokinesis failure. Cerebellum is the tissue showing highest sensitivity to CitK loss. The clinical phenotype of CitK knockout mice is significantly resued by P53 inactivation. In addition, CitK/P53 double knockout brains have almost normal levels of apoptosis, but display high percentage of binucleated and multinucleated cells. The aim of this study was to analyze the gene expression changes produced in developing neural tissue by CitK loss and to determine which alterations are P53-dependent. expression changes Methods: We analyzed by RNA sequencing total RNA extracted from P4 cerebellum of mice characterized by the following genotypes: 1. CitK +/-, P53 +/- (CTRL); 2. CitK -/-, P53 +/- (CitK-KO); 3. CitK +/-, P53 -/- (P53-KO); 4. CitK -/-, P53 -/- (D-KO). Biological triplicates were analyzed per every genotype. Conclusions: The loss of CitK leads to a strong reduction of the expression of pro-neural genes and induces a P53-related pro-apoptotic gene sets. The analysis of D-KO mice reveals that most of these changes are P53-dependent, but many genes implicated in growth arrest are induced through P53-independent mechanisms. Overall design: Cerebellar mRNA profiles of 4-day old mice of CTRL, CitK-KO, P53-KO and D-KO mice were generated by deep sequencing, in triplicate, using Illumina HiScan SQ

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Ghouzzi VE, Bianchi FT, Molineris I, Mounce BC, Berto GE, Rak M, Lebon S, Aubry L, Tocco C, Gai M, Chiotto AM, Sgrò F, Pallavicini G, Simon-Loriere E, Passemard S, Vignuzzi M, Gressens P, Di Cunto F