Zfp281 Shapes the Transcriptome of Trophoblast Stem Cells and Is Essential for Placental Development

Summary: Placental development is a key event in mammalian reproduction and embryogenesis. However, the molecular basis underlying placental development is not fully understood. Here, we conduct a forward genetic screen to identify regulators for extraembryonic development and identify Zfp281 as a key factor. Zfp281 overexpression in mouse embryonic stem cells facilitates the induction of trophoblast stem-like cells. Zfp281 is preferentially expressed in the undifferentiated trophoblast stem cell population in an FGF-dependent manner, and disruption of Zfp281 in mice causes severe defects in early placental development. Consistently, Zfp281-depleted trophoblast stem cells exhibit defects in maintaining the transcriptome and differentiation capacity. Mechanistically, Zfp281 interacts with MLL or COMPASS subunits and occupies the promoters of its target genes. Importantly, ZNF281, the human ortholog of this factor, is required to stabilize the undifferentiated status of human trophoblast stem cells. Thus, we identify Zfp281 as a conserved factor for the maintenance of trophoblast stem cell plasticity. : Ishiuchi et al. demonstrate that Zfp281 regulates gene expression through the interaction with MLL or COMPASS in trophoblast stem (TS) cells. Depletion of Zfp281 impairs TS cell plasticity in vitro and in vivo. Knockdown of ZNF281 downregulates a set of genes enriched in undifferentiated human TS cells, including ELF5 and LIN28A. Keywords: Zfp281, trophoblast stem cell, placental development, MLL-COMPAS

Electrolyte-gated-organic field effect transistors functionalized by lipid monolayers with tunable pH sensitivity for sensor applications

International audienceElectrolyte-gated organic field effect transistors (EG-OFETs) functionalized by engineered lipid monolayers (LMLs) are investigated to tune pH sensitivity for sensor application. The EG-OFET functionalized by OH-terminated LML shows linear dependence on the physiological pH range (4-8). Meanwhile, the LML with polar-head groups presents limited pH sensitivity only in a certain pH range. In contrast, the methyltrichlorosilane (MTS) passivation of the LML head-group makes the EG-OFET non sensitive in a broad pH range (1.68-12). These findings suggest that our proposed transistors have the potential to construct versatile sensor applications with the controllable pH sensitivity

Prominent Steatosis with Hypermetabolism of the Cell Line Permissive for Years of Infection with Hepatitis C Virus

<div><p>Most of experiments for HCV infection have been done using lytic infection systems, in which HCV-infected cells inevitably die. Here, to elucidate metabolic alteration in HCV-infected cells in a more stable condition, we established an HCV-persistently-infected cell line, designated as HPI cells. This cell line has displayed prominent steatosis and supported HCV infection for more than 2 years, which is the longest ever reported. It enabled us to analyze metabolism in the HCV-infected cells integrally combining metabolomics and expression arrays. It revealed that rate-limiting enzymes for biosynthesis of cholesterol and fatty acids were up-regulated with actual increase in cholesterol, desmosterol (cholesterol precursor) and pool of fatty acids. Notably, the pentose phosphate pathway was facilitated with marked up-regulation of glucose-6-phosphate dehydrogenase, a rete-limiting enzyme, with actual increase in NADPH. In its downstream, enzymes for purine synthesis were also up-regulated resulting in increase of purine. Contrary to common cancers, the TCA cycle was preferentially facilitated comparing to glycolysis pathway with a marked increase of most of amino acids. Interestingly, some genes controlled by nuclear factor (erythroid-derived 2)-like 2 (Nrf2), a master regulator of antioxidation and metabolism, were constitutively up-regulated in HPI cells. Knockdown of Nrf2 markedly reduced steatosis and HCV infection, indicating that Nrf2 and its target genes play important roles in metabolic alteration and HCV infection. In conclusion, HPI cell is a <i>bona fide</i> HCV-persistently-infected cell line supporting HCV infection for years. This cell line sustained prominent steatosis in a hypermetabolic status producing various metabolites. Therefore, HPI cell is a potent research tool not only for persistent HCV infection but also for liver metabolism, overcoming drawbacks of the lytic infection systems.</p></div

TCA cycle, amino acid metabolism, and the urea cycle.

<p>(<b>A</b>) A metabolic map of the TCA cycle, amino acid metabolism, and the urea cycle with gene expression is depicted in the same way as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0094460#pone-0094460-g004" target="_blank">Figure 4</a>. Underlined: essential amino acid. †: Metabolite appearing more than twice in this figure. Abbreviations: Cys, cysteine; Ala, alanine; Glu, glutamate; 2OG, 2-oxoglutarate; Leu, leucine; Lys, lysine; Trp, tryptophan; Gln, glutamine; Pro, proline; Arg, arginine; His, histidine; Met, methionine; Val, valine; Ile, isoleucine; Phe, phenylalanine; Tyr, tyrosine; Asp, aspartate; NAA, N-acetylaspartate; CAA, N-carbamoyl aspartate; CP, carbamoyl phosphate; NH3, ammonia. Symbols (¶, *, N.D., n.a.) represent the same meaning as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0094460#pone-0094460-g004" target="_blank">Figure 4A</a>. (<b>B</b>) Immunoblot analysis of the selected enzymes. The control was the same beta-actin as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0094460#pone-0094460-g004" target="_blank">Figure 4B</a>.</p

HPI cells supported HCV infection more than a year after establishment.

<p>(<b>A</b>) HCV core protein concentration in the medium was determined after the establishment of HPI cell. At time points indicated in Roman numerals, immunofluorescence staining for HCV was performed (B). Infectivity of HCVcc in the medium is shown above the graph. P-numbers in parentheses represent passage numbers after the establishment of HPI cell. (<b>B</b>) Immunofluorescence staining for HCV NS5A protein in the cells was performed.</p

Biosynthetic pathway of cholesterol.

<p>(<b>A</b>) Relative quantities of metabolites in Huh7.5 (left column) cells and HPI cells (right column) are superimposed on a metabolic map of the cholesterol biosynthesis pathway according to the data (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0094460#pone.0094460.s004" target="_blank">Table S1</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0094460#pone.0094460.s005" target="_blank">Table S2</a>). The metabolic map is depicted based on KEGG pathways (<a href="http://www.genome.jp/keg/" target="_blank">http://www.genome.jp/keg/</a>). The NADPH/NADP+ reaction, if associated, was added to the main reaction. Height of column with larger quantity is set to 100%, and that of smaller quantity are shown proportionally. Numbers on the right columns indicate the fold-change of HPI compared to Huh7.5, and the color of the column represents: yellow (> = 1.4-fold), blue ( = <0.7-fold), or gray (0.7∼1.4-fold). ¶: A metabolite appearing on other figure. Genes (italicized) located between metabolites encode enzyme(s) for a corresponding reaction with fold-expressions of HPI to Huh7.5 according to the data (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0094460#pone.0094460.s006" target="_blank">Table S3</a>). A gene encoding a rate-limiting enzyme is surrounded by a square. *: Immunoblot analysis was also done for confirmation in (B). N.D.: Not detected. n.a.: Not assessed because of low expression. (<b>B</b>) Immunoblot analysis of the selected enzymes. Beta-actin was used as a control.</p

Intracellular concentration of NAD(P)+ and NAD(P)H.

<p>Numeral in a parenthesis indicates relative area by the CE-FOFMS.</p