Development of gene expression signatures for identifying novel factors that can overcome age-associated reprogramming barriers
ABSTRACT: To investigate the molecular features underlying senescence and rejuvenation during aged cell reprogramming and identify novel factors that can overcome age-associated barriers, we compared gene expression for reprogramming intermediates on D8 of tail-tip fibroblasts (TTFs) from young Wild Type (WT), old WT, and old p16 knockout (KO) mice. We collected TTFs from young WT, old WT, and old p16 KO mice and reprogrammed the cells by introducing four reprogramming factors, including Oct4, Sox2, Klf4, and c-Myc. Gene expression of reprogramming intermediates on D8 were compared. Two independent experiments were performed using different mice donors for each experiment.
Project description:To compare the transcriptional profile of endogenous Sertoli cells from different Stage of Sertoli cell development (embryonic, immature, mature) to the transcriptionla profile of induced embryonic Sertoli cells derived from MEFs or TTFs we employed the agilent whole genome microarray Keywords: Expression profiling by array The following samples were analyzed in duplicates (MEFs, TTFs, ieSCs (derived from MEFs), ieSCs (derived from TTFs), 14.5 dpc male gonad, immature Sertoli (19 dpc embryo testis) and mature (8 week-old mouse testis))
Project description:Transcriptional profiling of p16-induced senescent human diploid fibroblasts compared with proliferating cells. TIG-3 ER-p16 cells (primary normal human diploid fibroblasts expressing a 4-hydroxytamoxifen(4-OHT) regulatable form of human p16) were cultured for 7 days with or without 4-OHT. Total RNA was isolated using TRIzol reagent and were analyzed using the hum
Project description:X chromosome inactivation (XCI) compensates for differences in X-chromosome number between male and female mammals. XCI is orchestrated by Xist RNA, whose expression in early development leads to transcriptional silencing of one X-chromosome in the female. Knockout studies have established a requirement for Xist, with inviability of female embryos that inherit an Xist deletion from the father. Here, we report that female mice lacking Xist RNA can, surprisingly, develop and survive to term. Xist-null females are born at lower frequency and are smaller at birth, but organogenesis is mostly normal. Transcriptomic analysis indicates significant overexpression of hundreds of X-linked genes across multiple tissues. Therefore, Xist-null mice can develop to term in spite of a deficiency of dosage compensation. However, the degree of X-autosomal dosage imbalance was less than anticipated (1.14- to 1.36-fold). Thus, partial dosage compensation can be achieved without Xist, supporting the idea of inherent genome balance. Nevertheless, to date, none of the mutant mice has survived beyond weaning stage. Sudden death is associated with failure of postnatal organ maturation. Our data suggest Xist-independent mechanisms of dosage compensation and demonstrate that small deviations from X-autosomal balance can have profound effects on overall fitness. RNA-sequencing of tail-tip fibroblasts (TTFs), spleen, liver and heart tissue from Xist-null and control female mice. Sequencing performed with 50nt read length on Illumina HiSeq2000 or 2500. Data consists of 3 biological replicates for TTFs (6 datasets) and 2 biological replicates for tissues (12 datasets).
Project description:Plasticity of differentiated cells has been proved by nuclear transfer, induced pluripotent cells and transdifferentiation. Here we show that by transduction of 3 factors (Hnf1alpha, Gata4, and Foxa3) and p19Arf inactivation, tail-tip fibroblasts can be converted to hepatocyte-like (iHep) cells, expressing hepatocyte marker genes, and acquiring many mature hepatocyte functions in vitro and in vivo. p19Arf-null TTFs were tranfected with 3 liver enriched transcription factors, then changed to modified Block's medium. To enrich iHep cells, epithelial cells were enriched by partial trypsin digestion.
Project description:Early invasive growth and metastasis are features of pancreatic cancer that rely on resistance to anoikis, an apoptosis program activated upon loss of adequate matrix anchorage. Re-expression of the tumor suppressor p16 reversed anoikis resistance of pancreatic cancer cells. This conversion to an anoikis-susceptible phenotype was found to be associated with a striking loss of GNE mRNA expression, prompting us to address the role of GNE in pancreatic cancer in more detail. GNE catalyzes a rate-limiting key step of the sialic acid biosynthesis and may have additional functions in the nucleus. Pancreatic cancer cells Capan-1. Three p16-transfectants and three mock-transfectants.
Project description:We found mitoflash has function in reprogramming. So we examined the genes expression after activation of mitoflash during somatic cell reprogramming. There are two ways to improve the mitoflash. First we overexpressed CypD, a mPTP component, to improve the mitoflash. Second we used the durgs, mastoparan and paraquat to increase the mitoflash. The MEF cells were reprogrammed, and treatment with mastoparan, paraquat or overexpressed with CypD. After activation of mitoflash at different times, the cells were collected for RNA-Seq. MEF cells were reprogrammed and expressed with CypD and Flag (as control) for 4 days. The cells were collected for RNA-Seq (Samples: Falg-D4, CypD-D4). MEF cells were reprogrammed and treated with mastoparan and paraquat for 8 days. The cells were collected for RNA-Seq (Samples: control-D8, mastoparan-D8 and paraquat-D8).
Project description:The superior olivary complex (SOC) is a prominent auditory brainstem center and represents one of the prime model systems to study the development of sensory circuits. We recently performed genome-wide microarray studies to analyze the SOC-related genetic program at postnatal day (P)4 and P25. Here, we extended this analysis by including two additional time points, P0 and P16. Data sets were validated by qRT-PCR. Statistical analysis were performed for the different developmental time points as well as with for differences between the SOC and our previously analyzed brain samples. This analysis revealed that after hearing-onset (P16 and P25), 918 oligos were up-regulated and 810 oligos down-regulated in the SOC compared to the two prehearing stages (P0 and P4). Of the up-regulated oligos, 530 were significantly higher expressed compared to the brain at P25. Concerning neurotransmission, SOC-related elevation was mainly observed for K+ channels, G-proteins, and myelination-related proteins, whereas Ca2+-related proteins showed a decreased expression. In the pre-hearing period, 47 oligos were up-regulated compared to the brain. Several of them were transcription factors, previously associated with other auditory structures, and might ensure coordinated development of peripheral and central auditory structures. Stage-specific comparison identified distinct genetic programs during development: Circuit formation/refinement at P4; myelination and circuit refinement/consolidation at P16; and neuroprotection at P25. Altogether, our study defines the genetic program of postnatal SOC development and provides strong functional candidates for various developmental processes. The genome wide expression during the postnatal development of the SOC was investigated at two different time points: at postnatal (P) day 0 (before hearing onset) and P16 (after hearing onset). Samples were hybridized onto two color platforms. At least 6 up to nine biological replicates per sample were performed.
Project description:p16 and p21 act as tumor suppressors through induction of cellular senescence. However, senescence-independent roles of these CDK inhibitors are not known. To identify the mechanism responsible for the failure of Mo-MDSCs (monocytic myeloid-derived suppressor cells) infiltration into tumor allografts in p16/p21-double knockout (DKO) mice, we searched for chemokine receptors that were highly expressed in Mo- but not PMN-MDSCs (polymorphonuclear myeloid-derived suppressor cells) and were downregulated in p16/p21-DKO as compared to WT Mo-MDSCs. Ccr2, Ccr5, and Cx3cr1 were identified by RNA-seq analysis. Overall design: RNA sequencing was performed using PMN-MDSCs derived from wild-type mice (WT), Mo-MDSCs derived from WT mice and Mo-MDSCs derived from p16/p21 DKO mice in triplicates, respectively.
Project description:The superior olivary complex (SOC) is an essential auditory brainstem structure involved in sound localization. In order to identify the genetic program underlying its maturation, we profiled the transcriptome of the rat SOC at postnatal days (P)0, P4, P16, and P25, using genome-wide microarrays (41,012 sequences). Differences in gene expression between two consecutive stages were highest between P4 versus P16 (3.6%), but dropped to 0.06% between P16 versus P25. To identify SOC-related genetic programs, we also profiled the brain at P4 and P25. Differentially expressed sequences between SOC and brain almost doubled from P4 (4.4%) to P25 (7.6%). These datademonstrate considerable molecular specification around hearing onset, which is rapidly finalized. Prior to hearing onset, several transcription factors associated with the peripheral auditory system were up-regulated, likely coordinating auditory system development. Additionally, serotonin-related genes and crystalline-gamma subunits were highly expressed. The molecular repertoire of mature neurons was sculpted by SOC-related up- and down-regulation of several protein categories, among which voltage-gated channels and myelination were prominent. Comparison with the brain revealed a significant enrichment of deafness-related oligos in the SOC-related genetic program (26 in the SOC, only 11 in the brain). Furthermore, 29 out of 453 SOC-related oligos mapped within 19 genetic intervals associated with hearing impairment. Together, we identified sequential genetic programs in the SOC, thereby pinpointing candidates which may guide its development and ensure proper function. The enrichment of deafness-related genes in the SOC may have implications for restoring hearing, as central auditory structures might be more severely affected than previously appreciated. This SuperSeries is composed of the SubSeries listed below. The genome wide expression during the postnatal development of the SOC was investigated at four different time points: at postnatal (P) day 0, P4, P16 and P25. Concerning the brain, P4 and P25 were used. Samples were hybridized onto two color platforms. At least 6 up to nine biological replicates per sample were performed.