Gene expression profiles of heterozygous periphilin knockout mice compared to wt littermates

Periphilin is a protein which is involved in multiple processes in vivo, including terminal differentiation of keratinozytes as well as cell-cycle and cancer related functions. Here we generated mice with a targeted disruption of the periphilin-1 gene to explore its physiological role from an organismic perspective. In accordance with a ubiquitous expression of periphilin in the murine embryo, the homozygous deficiency of periphilin is lethal in early embryogenesis. We therefore characterized mice with a disruption of only one periphilin allele. As heterozygous periphilin knockout mice show no obvious histological alterations and have no apparent behavioural phenotypes, we compared whole transcriptome RNA expression profiles of total brain tissue of periphilin+/- knockout mice and wild type littermates for an in-depth analysis of heterozygous animals. In periphilin+/- knockout mice, 3 probe sets were indicative of significant differential expression (p ≤ 0.05, SLR ≥ 1 which is equivalent to 2 fold). Two of these probe sets (1438864_at and 1439170_at) refer to unannotated or unclassifiable genes. According to the NetAffx™ Analysis Center, the third probe set (1447831_s_at) is assigned to myotubularin related protein 7 (Mtmr7). The probe set, however, lies upstream of the Mtmr7 gene (Ensembl gene ENSMUSG00000039431), and its signal is therefore not representative for the Mtmr7 gene. Quantitative RT-PCR (qRT-PCR) analysis with a primer set specific for Mtmr7 confirmed that its expression is not altered in periphilin+/- knockout mice (relative expression compared to wild type: 0.924; p = 0.419). In summary, none of more than 45.000 covered transcripts is differentially expressed in periphilin+/- knockout mice in comparison to wild type littermates. Whole brains of three male 2-months-old periphilin+/-knockout mice and three C57BL/6-wild type littermates