Oocyte quality is enhanced by hypoglycosylated FSH through increased cell-to-cell interaction during mouse follicle development.

Macroheterogeneity in follicle-stimulating hormone (FSH) ß-subunit N-glycosylation results in distinct FSH glycoforms. Hypoglycosylated FSH21 is the abundant and more bioactive form in pituitaries of females under 35 years of age, whereas fully glycosylated FSH24 is less bioactive and increases with age. To investigate whether the shift in FSH glycoform abundance contributes to the age-dependent decline in oocyte quality, the direct effects of FSH glycoforms on folliculogenesis and oocyte quality were determined using an encapsulated in vitro mouse follicle growth system. Long-term culture (10-12 days) with FSH21 (10 ng/ml) enhanced follicle growth, estradiol secretion and oocyte quality compared with FSH24 (10 ng/ml) treatment. FSH21 enhanced establishment of transzonal projections, gap junctions and cell-to-cell communication within 24 h in culture. Transient inhibition of FSH21-mediated bidirectional communication abrogated the positive effects of FSH21 on follicle growth, estradiol secretion and oocyte quality. Our data indicate that FSH21 promotes folliculogenesis and oocyte quality in vitro by increasing cell-to-cell communication early in folliculogenesis, and that the shift in in vivo abundance from FSH21 to FSH24 with reproductive aging may contribute to the age-dependent decline in oocyte quality.

The effects of short-term and long-term phthalate exposures on ovarian follicle growth dynamics and hormone levels in female mice†.

Di(2-ethylhexyl) phthalate and diisononyl phthalate are widely used as plasticizers in polyvinyl chloride products. Short-term exposures to phthalates affect hormone levels, ovarian follicle populations, and ovarian gene expression. However, limited data exist regarding the effects of long-term exposure to phthalates on reproductive functions. Thus, this study tested the hypothesis that short-term and long-term exposure to di(2-ethylhexyl) phthalate or diisononyl phthalate disrupts follicle dynamics, ovarian and pituitary gene expression, and hormone levels in female mice. Adult CD-1 female mice were exposed to vehicle, di(2-ethylhexyl) phthalate, or diisononyl phthalate (0.15 ppm, 1.5 ppm, or 1500 ppm) via the chow for 1 or 6 months. Short-term exposure to di(2-ethylhexyl) phthalate (0.15 ppm) and diisononyl phthalate (1.5 ppm) decreased serum follicle-stimulating hormone levels compared to control. Long-term exposure to di(2-ethylhexyl) phthalate and diisononyl phthalate (1500 ppm) increased the percentage of primordial follicles and decreased the percentages of preantral and antral follicles compared to control. Both phthalates increased follicle-stimulating hormone levels (di(2-ethylhexyl) phthalate at 1500 ppm; diisononyl phthalate at 1.5 ppm) and decreased luteinizing hormone levels (di(2-ethylhexyl) phthalate at 0.15 and 1.5 ppm; diisononyl phthalate at 1.5 ppm and 1500 ppm) compared to control. Furthermore, both phthalates altered the expression of pituitary gonadotropin subunit genes (Cga, Fshb, and Lhb) and a transcription factor (Nr5a1) that regulates gonadotropin synthesis. These data indicate that long-term exposure to di(2-ethylhexyl) phthalate and diisononyl phthalate alters follicle growth dynamics in the ovary and the expression of gonadotropin subunit genes in the pituitary and consequently luteinizing hormone and follicle-stimulating hormone synthesis.

Nanoscale phase separation on an AlGaN surface characterized by scanning diffusion microscopy.

AlGaN is an important material for deep ultraviolet optoelectronic devices and electronic devices. The phase separation on the AlGaN surface means small-scale compositional fluctuations of Al, which is prone to degrade the performance of devices. In order to study the mechanism of the surface phase separation, the Al0.3Ga0.7N wafer was investigated by the scanning diffusion microscopy method based on the photo-assisted Kelvin force probe microscope. The response of the surface photovoltage near the bandgap was quite different for the edge and the center of the island on the AlGaN surface. We utilize the theoretical model of scanning diffusion microscopy to fit the local absorption coefficients from the measured surface photovoltage spectrum. During the fitting process, we introduce as and ab parameters (bandgap shift and broadening) to describe the local variation of absorption coefficients α(as, ab, λ). The local bandgap and Al composition can be calculated quantitatively from the absorption coefficients. The results show that there is lower bandgap (about 305 nm) and lower Al composition (about 0.31) at the edge of the island, compared with those at the center of the island (about 300 nm for bandgap and 0.34 for Al composition). Similar to the edge of the island, there is a lower bandgap at the V-pit defect which is about 306 nm corresponding to the Al composition of about 0.30. These results mean Ga enrichment both at the edge of the island and the V-pit defect position. It proves that scanning diffusion microscopy is an effective method to review the micro-mechanism of AlGaN phase separation.

Size-dependent sidewall defect effect of GaN blue micro-LEDs by photoluminescence and fluorescence lifetime imaging.

Sidewall defects play a key role in determining the efficiency of GaN-based micro-light emitting diodes (LEDs) for next generation display applications, but there still lacks direct observation of defects-related recombination at the affected area. In this Letter, we proposed a direct technique to investigate the recombination mechanism and size effect of sidewall defects for GaN blue micro-LEDs. The results show that mesa etching will produce stress release near the sidewall, which can reduce the quantum confinement Stark effect (QCSE) to improve the radiative recombination. Meanwhile, the defect-related non-radiative recombination generated by the sidewall defects plays a leading role under low-power injection. In addition, the effective area of the mesas affected by the sidewall defects can be directly observed according to the fluorescence lifetime imaging microscope (FLIM) characterization. For example, the effective area of the mesa with 80 µm is affected by 23% while the entire area of the mesa with 10 µm is almost all affected. This study provides guidance for the analysis and repair of sidewall defects to improve the quantum efficiency of micro-LEDs display at low current density.

Photosystems and antioxidative system of rye, wheat and triticale under Pb stress.

Lead (Pb2+) pollution in the soil sub-ecosystem has been a continuously growing problem due to economic development and ever-increasing anthropogenic activities across the world. In this study, the photosynthetic performance and antioxidant capacity of Triticeae cereals (rye, wheat and triticale) were compared to assess the activities of antioxidants, the degree of oxidative damage, photochemical efficiency and the levels of photosynthetic proteins under Pb stress (0.5 mM, 1 mM and 2 mM Pb (NO3)2). Compared with triticale, Pb treatments imposed severe oxidative damage in rye and wheat. In addition, the highest activity of major antioxidant enzymes (SOD, POD, CAT, and GPX) was also found to be elevated. Triticale accumulated the highest Pb contents in roots. The concentration of mineral ions (Mg, Ca, and K) was also high in its leaves, compared with rye and wheat. Consistently, triticale showed higher photosynthetic activity under Pb stress. Immunoblotting of proteins revealed that rye and wheat have significantly lower levels of D1 (photosystem II subunit A, PsbA) and D2 (photosystem II subunit D, PsbD) proteins, while no obvious decrease was noticed in triticale. The amount of light-harvesting complex II b6 (Lhcb6; CP24) and light-harvesting complex II b5 (Lhcb5; CP26) was significantly increased in rye and wheat. However, the increase in PsbS (photosystem II subunit S) protein only occurred in wheat and triticale exposed to Pb treatment. Taken together, these findings demonstrate that triticale shows higher antioxidant capacity and photosynthetic efficiency than wheat and rye under Pb stress, suggesting that triticale has high tolerance to Pb and could be used as a heavy metal-tolerant plant.

Quantum Effects Enter Semiconductor-Based SERS: Multiresonant MoO3·xH2O Quantum Dots Enabling Direct, Sensitive SERS Detection of Small Inorganic Molecules.

There is keen research interest in building highly effective semiconductor-based surface-enhanced Raman scattering (SERS) platforms, due to their selectivity for many probe molecules and suitability for complex scenario applications. However, current tuning approaches have not yet been successful in creating semiconductor-based SERS sensors for small inorganic molecules, due to the challenge of creating sufficient SERS enhancement in semiconductors. Here, we demonstrate the use of MoO3·xH2O quantum dots (QDs), to achieve direct and sensitive fingerprinting of the inorganic species hydrazine, which is a first attempt in semiconductor-based SERS research, as well as various other probe molecules. The resulting SERS platform that uses QDs with average size of 2.2 nm could successfully detect the signal of hydrazine with a limit of detection estimated to be around 4 × 10-5 M, significantly lowering the detectable concentration by at least 1000-fold, in sharp contrast to the weak performance of 10 and 100 nm particles, demonstrating that quantum size effect triggered by small particle size below the Bohr radius is crucially responsible for high SERS activity. The significantly enhanced SERS activity is a result of vibronically coupled multipathway, highly efficient charge-transfer resonances induced by the divergence of energy states in quantum-sized MoO3·xH2O. This is a proof-of-concept demonstration of the exploitation of quantum size effect, toward significantly enhanced intrinsic SERS activity in semiconductor-based SERS materials.

Unexpected Parabolic Temperature Dependency of CH4 Emissions from Rice Paddies.

Global warming is expected to affect methane (CH4) emissions from rice paddies, one of the largest human-induced sources of this potent greenhouse gas. However, the large variability in warming impacts on CH4 emissions makes it difficult to extrapolate the experimental results over large regions. Here, we show, through meta-analysis and multi-site warming experiments using the free air temperature increase facility, that warming stimulates CH4 emissions most strongly at background air temperatures during the flooded stage of ∼26 °C, with smaller responses of CH4 emissions to warming at lower and higher temperatures. This pattern can be explained by divergent warming responses of plant growth, methanogens, and methanotrophs. The effects of warming on rice biomass decreased with the background air temperature. Warming increased the abundance of methanogens more strongly at the medium air temperature site than the low and high air temperature sites. In contrast, the effects of warming on the abundance of methanotrophs were similar across the three temperature sites. We estimate that 1 °C warming will increase CH4 emissions from paddies in China by 12.6%─substantially higher than the estimates obtained from leading ecosystem models. Our findings challenge model assumptions and suggest that the estimates of future paddy CH4 emissions need to consider both plant and microbial responses to warming.

Th1 Cells Rolling on Selectins Trigger DAP12-Dependent Signals That Activate Integrin αLß2.

During inflammation, both neutrophils and effector T cells use selectins to roll and integrins to arrest in postcapillary venules. In both cell types, chemokines can transduce signals that convert integrin αLß2 to a high-affinity conformation, which interacts with ICAM-1 to mediate arrest. In neutrophils, selectins also trigger an immunoreceptor-like signaling cascade that converts integrin αLß2 to an intermediate-affinity conformation, which interacts with ICAM-1 to slow rolling. It is not known whether selectins induce similar signaling events in T cells. Ag engagement causes phosphorylation of ITAMs on the TCR; these motifs recruit kinases and adaptors that lead to the activation of αLß2. We found that mouse Th1 cells rolling on P- or E-selectin triggered signals that promoted αLß2-dependent slow rolling on ICAM-1 in vitro and in vivo. The selectin signaling cascade resembled that used by the TCR, except that unexpectedly, Th1 cells employed the ITAM-bearing protein DAP12, which was not known to be expressed in these cells. Importantly, outside-in signaling through ligand-occupied αLß2 also required DAP12. Cooperative selectin and chemokine signaling in Th1 cells promoted αLß2-dependent slow rolling and arrest in vitro and in vivo and migration into Ag-challenged tissues in vivo. Our findings reveal an important function for DAP12 in Th1 cells and a new mechanism to recruit effector T cells to sites of inflammation.

Magnetic deep eutectic solvents: formation and properties.

Deep eutectic solvents (DESs) are well-known as novel solvents due to their unique properties, which are indispensable for the development of green chemistry in the future. CoCl2·6H2O and NiCl2·6H2O-based DESs, which could be called magnetic DESs (MDESs) for short in view of their responsive behavior to an external magnetic field, have been widely used in many industrial applications, such as biomass treatment, electrolytes, and material preparation. For better application and full-scale development of these MDESs in various fields, eleven MDESs were prepared in this work by using CoCl2·6H2O and NiCl2·6H2O as hydrogen bond acceptors (HBAs) with alcohols, carboxylic acids and amides as hydrogen bond donors (HBDs), respectively. The intermolecular interactions between the components of MDESs were characterized via FTIR, 1H NMR and DSC analysis. In addition, physicochemical properties including density, viscosity, conductivity, ionicity, pH values, surface tension, thermostability and solvatochromic parameters were investigated. All MDESs exhibit acid characteristics and have good conductivity comparable with ionic liquids (ILs) and other DESs used for electrolytes. The results show that stronger H-bonding networks in Ni-based MDESs make them have higher density, viscosity, polarity and surface tension values than Co-based MDESs. Moreover, all prepared MDESs possess a good conductivity behavior which could be comparable to that of common organic solvents and ILs. According to this work, we could better comprehend the behavior of Co/Ni-based MDESs and choose the appropriate one for particular applications.

Characterization, Pathogenicity, Phylogeny, and Comparative Genomic Analysis of Pseudomonas tolaasii Strains Isolated from Various Mushrooms in China.

Since 2016, devastating bacterial blotch affecting the fruiting bodies of Agaricus bisporus, Cordyceps militaris, Flammulina filiformis, and Pleurotus ostreatus in China has caused severe economic losses. We isolated 102 bacterial strains and characterized them polyphasically. We identified the causal agent as Pseudomonas tolaasii and confirmed the pathogenicity of the strains. A host range test further confirmed the pathogen's ability to infect multiple hosts. This is the first report in China of bacterial blotch in C. militaris caused by P. tolaasii. Whole-genome sequences were generated for three strains: Pt11 (6.48 Mb), Pt51 (6.63 Mb), and Pt53 (6.80 Mb), and pangenome analysis was performed with 13 other publicly accessible P. tolaasii genomes to determine their genetic diversity, virulence, antibiotic resistance, and mobile genetic elements. The pangenome of P. tolaasii is open, and many more gene families are likely to emerge with further genome sequencing. Multilocus sequence analysis using the sequences of four common housekeeping genes (glns, gyrB, rpoB, and rpoD) showed high genetic variability among the P. tolaasii strains, with 115 strains clustered into a monophyletic group. The P. tolaasii strains possess various genes for secretion systems, virulence factors, carbohydrate-active enzymes, toxins, secondary metabolites, and antimicrobial resistance genes that are associated with pathogenesis and adapted to different environments. The myriad of insertion sequences, integrons, prophages, and genome islands encoded in the strains may contribute to genome plasticity, virulence, and antibiotic resistance. These findings advance understanding of the determinants of virulence, which can be targeted for the effective control of bacterial blotch disease.

Lhb-/-Lhr-/- Double Mutant Mice Phenocopy Lhb-/- or Lhr-/- Single Mutants and Display Defects in Leydig Cells and Steroidogenesis.

In the mouse, two distinct populations of Leydig cells arise during testis development. Fetal Leydig cells arise from a stem cell population and produce T required for masculinization. It is debated whether they persist in the adult testis. A second adult Leydig stem cell population gives rise to progenitor-immature-mature adult type Leydig cells that produce T in response to LH to maintain spermatogenesis. In testis of adult null male mice lacking either only LH (Lhb-/-) or LHR (Lhr-/-), mature Leydig cells are absent but fetal Leydig cells persist. Thus, it is not clear whether other ligands signal via LHRs in Lhb null mice or LH signals via other receptors in the absence of LHR in Lhr null mice. Moreover, it is not clear whether truncated LHR isoforms generated from the same Lhr gene promoter encode functionally relevant LH receptors. To determine the in vivo roles of LH-LHR signaling pathway in the Leydig cell lineage, we generated double null mutant mice lacking both LH Ligand and all forms of LHR. Phenotypic analysis indicated testis morpho-histological characteristics are identical among double null and single mutants which all showed poorly developed interstitium with a reduction in Leydig cell number and absence of late stage spermatids. Gene expression analyses confirmed that the majority of the T biosynthesis pathway enzyme-encoding mRNAs expressed in Leydig cells were all suppressed. Expression of thrombospondin-2, a fetal Leydig cell marker gene was upregulated in single and double null mutants indicating that fetal Leydig cells originate and develop independent of LH-LHR signaling pathway in vivo. Serum and intratesticular T levels were similarly suppressed in single and double mutants. Consequently, expression of AR-regulated genes in Sertoli and germ cells were similarly affected in single and double mutants without any evidence of any additive effect in the combined absence of both LH and LHR. Our studies unequivocally provide genetic evidence that in the mouse testis, fetal Leydig cells do not require LH-LHR signaling pathway and a one-to-one LH ligand-LHR signaling pathway exists in vivo to regulate adult Leydig cell lineage and spermatogenesis.

Sink Strength Promoting Remobilization of Non-Structural Carbohydrates by Activating Sugar Signaling in Rice Stem during Grain Filling.

The remobilization of non-structural carbohydrates (NSCs) in the stem is essential for rice grain filling so as to improve grain yield. We conducted a two-year field experiment to deeply investigate their relationship. Two large-panicle rice varieties with similar spikelet size, CJ03 and W1844, were used to conduct two treatments (removing-spikelet group and control group). Compared to CJ03, W1844 had higher 1000-grain weight, especially for the grain growth of inferior spikelets (IS) after removing the spikelet. These results were mainly ascribed to the stronger sink strength of W1844 than that of CJ03 contrasting in the same group. The remobilization efficiency of NSC in the stem decreased significantly after removing the spikelet for both CJ03 and W1844, and the level of sugar signaling in the T6P-SnRK1 pathway was also significantly changed. However, W1844 outperformed CJ03 in terms of the efficiency of carbon reserve remobilization under the same treatments. More precisely, there was a significant difference during the early grain-filling stage in terms of the conversion of sucrose and starch. Interestingly, the sugar signaling of the T6P and SnRK1 pathways also represented an obvious change. Hence, sugar signaling may be promoted by sink strength to remobilize the NSCs of the rice stem during grain filling to further advance crop yield.

Cooperative PSGL-1 and CXCR2 signaling in neutrophils promotes deep vein thrombosis in mice.

Inflammation is a major contributor to deep vein thrombosis (DVT). Flow restriction of the inferior vena cava (IVC) in mice induces DVT like that in humans. In this model, P-selectin-dependent adhesion of neutrophils and monocytes leads to release of neutrophil extracellular traps (NETs) and expression of tissue factor. However, it is not known what signals cause myeloid cells to generate these procoagulant effectors. Using ultrasonography and spinning-disk intravital microscopy in genetically engineered mice, we found that engagement of P-selectin glycoprotein ligand-1 (PSGL-1) and the chemokine receptor CXCR2 on rolling neutrophils propagated signals that cooperated to induce ß2 integrin-dependent arrest in flow-restricted IVCs. Unlike previous reports, PSGL-1 signaling in neutrophils did not require L-selectin, and it used tyrosine 145 rather than tyrosines 112 and 128 on the adaptor Src homology domain-containing leukocyte phosphoprotein of 76 kDa. PSGL-1 and CXCR2 signaling cooperated to increase the frequency and size of thrombi, in part by stimulating release of NETs. Unlike in neutrophils, blocking PSGL-1 or CXCR2 signaling in monocytes did not affect their recruitment into thrombi or their expression of tissue factor. Our results demonstrate that neutrophils cooperatively signal through PSGL-1 and CXCR2 to promote DVT.

Sialylation on O-glycans protects platelets from clearance by liver Kupffer cells.

Most platelet membrane proteins are modified by mucin-type core 1-derived glycans (O-glycans). However, the biological importance of O-glycans in platelet clearance is unclear. Here, we generated mice with a hematopoietic cell-specific loss of O-glycans (HC C1galt1-/- ). These mice lack O-glycans on platelets and exhibit reduced peripheral platelet numbers. Platelets from HC C1galt1-/- mice show reduced levels of α-2,3-linked sialic acids and increased accumulation in the liver relative to wild-type platelets. The preferential accumulation of HC C1galt1-/- platelets in the liver was reduced in mice lacking the hepatic asialoglycoprotein receptor [Ashwell-Morell receptor (AMR)]. However, we found that Kupffer cells are the primary cells phagocytosing HC C1galt1-/- platelets in the liver. Our results demonstrate that hepatic AMR promotes preferential adherence to and phagocytosis of desialylated and/or HC C1galt1-/- platelets by the Kupffer cell through its C-type lectin receptor CLEC4F. These findings provide insights into an essential role for core 1 O-glycosylation of platelets in their clearance in the liver.

Melatonin improves K+ and Na+ homeostasis in rice under salt stress by mediated nitric oxide.

Rice (Oryza sativa L.) productivity is greatly affected by soil salinity and melatonin (MLT) has long been recognized as a positive molecule that can alleviate the damage caused by salt. Here, the role of nitric oxide (NO) in the regulation of salt tolerance by MLT was investigated in rice. MLT pretreatment increased the fresh and dry weight of rice seedlings under salt stress. Its beneficial effects include less relative electrolyte leakage (REL) and better K+/Na+ homeostasis. MLT increased the activity of nitric oxide synthase (NOS). The polyamines (PAs) content and the utilization of arginine were also increased, thereby increasing NO content in salt-stressed rice seedlings. Pharmacological approach showed that NO, as a necessary downstream signaling molecule, was involved in the regulation of MLT on the K+/Na+ homeostasis of rice. Under salt stress, MLT improved the H+-pumps activities in plasma membrane (PM) and vacuole membrane (VM) in roots, MLT also increased the ATP content of rice roots by increasing the NO content of rice. Thus, the efflux of Na+ and the influx of K+ were promoted. When endogenous NO was scavenged, the regulation of K+/Na+ homeostasis by MLT was blocked. Therefore, MLT mediated K+/Na+ homeostasis of rice under salt stress by mediating NO.

Rhodium-catalyzed reductive carbonylation of aryl iodides to arylaldehydes with syngas.

The reductive carbonylation of aryl iodides to aryl aldehydes possesses broad application prospects. We present an efficient and facile Rh-based catalytic system composed of the commercially available Rh salt RhCl3·3H2O, PPh3 as phosphine ligand, and Et3N as the base, for the synthesis of arylaldehydes via the reductive carbonylation of aryl iodides with CO and H2 under relatively mild conditions with a broad substrate range affording the products in good to excellent yields. Systematic investigations were carried out to study the experimental parameters. We explored the optimal ratio of Rh salt and PPh3 ligand, substrate scope, carbonyl source and hydrogen source, and the reaction mechanism. Particularly, a scaled-up experiment indicated that the catalytic method could find valuable applications in industrial productions. The low gas pressure, cheap ligand and low metal dosage could significantly improve the practicability in both chemical researches and industrial applications.

Recombinant FSH glycoforms are bioactive in mouse preantral ovarian follicles.

Female reproductive aging is characterized by a rise in follicle-stimulating hormone (FSH) levels during peri-menopause. N-linked glycans are co-translationally attached to the Asn7 and Asn24 residues on the FSHß subunit. Differences in the number of N-glycans on the FSHß subunit result in distinct glycoforms: hypo-glycosylated (FSH21/18, glycans absent on either Asn24 or Asn7, respectively) or fully-glycosylated (FSH24, glycans present on both Asn7 and Asn24). The relative abundance of FSH glycoforms changes with advanced reproductive age, shifting from predominantly FSH21/18 in younger women to FSH24 in older women. Previous in vitro studies in granulosa cell lines and in vivo studies using Fshb-null mice showed these glycoforms elicit differential bioactivities. However, the direct effects of FSH glycoforms on the mouse ovarian follicle have not yet been determined. In this study, we isolated secondary follicles from pre-pubertal mice and treated them with 20- or 100 ng/mL purified recombinant FSH glycoforms for 1 h or 18-20 h. Analysis of phosphorylated PKA substrates showed that glycoforms were bioactive in follicles following 1-h treatment, although differential bioactivity was only observed with the 100 ng/mL dose. Treatment of follicles with 100 ng/mL of each glycoform also induced distinct expression patterns of FSH-responsive genes as assessed by qPCR, consistent with differential function. Our results, therefore, indicate that FSH glycoforms are bioactive in isolated murine follicles.

Cutting Edge: Foxp1 Controls Naive CD8+ T Cell Quiescence by Simultaneously Repressing Key Pathways in Cellular Metabolism and Cell Cycle Progression.

Previously we have shown that transcription factor Foxp1 plays an essential role in maintaining naive T cell quiescence; in the absence of Foxp1, mature naive CD8(+) T cells proliferate in direct response to homeostatic cytokine IL-7. In this study, we report that the deletion of Foxp1 in naive CD8(+) T cells leads to enhanced activation of the PI3K/Akt/mammalian target of rapamycin signaling pathway and its downstream cell growth and metabolism targets in response to IL-7. We found that Foxp1 directly regulates PI3K interacting protein 1, a negative regulator of PI3K. Additionally, we found that deletion of Foxp1 in naive CD8(+) T cells results in increased expression levels of E2fs, the critical components for cell cycle progression and proliferation, in a manner that is not associated with increased phosphorylation of retinoblastoma protein. Taken together, our studies suggest that Foxp1 enforces naive CD8(+) T cell quiescence by simultaneously repressing key pathways in both cellular metabolism and cell cycle progression.

Replacing the Promoter of the Murine Gene Encoding P-selectin with the Human Promoter Confers Human-like Basal and Inducible Expression in Mice.

In humans and mice, megakaryocytes/platelets and endothelial cells constitutively synthesize P-selectin and mobilize it to the plasma membrane to mediate leukocyte rolling during inflammation. TNF-α, interleukin 1ß, and LPS markedly increase P-selectin mRNA in mice but decrease P-selectin mRNA in humans. Transgenic mice bearing the entire human SELP gene recapitulate basal and inducible expression of human P-selectin and reveal human-specific differences in P-selectin function. Differences in the human SELP and murine Selp promoters account for divergent expression in vitro, but their significance in vivo is not known. Here we generated knockin mice that replace the 1.4-kb proximal Selp promoter with the corresponding SELP sequence (Selp(KI)). Selp(KI) (/) (KI) mice constitutively expressed more P-selectin on platelets and more P-selectin mRNA in tissues but only slightly increased P-selectin mRNA after injection of TNF-α or LPS. Consistent with higher basal expression, leukocytes rolled more slowly on P-selectin in trauma-stimulated venules of Selp(KI) (/) (KI) mice. However, TNF-α did not further reduce P-selectin-dependent rolling velocities. Blunted up-regulation of P-selectin mRNA during contact hypersensitivity reduced P-selectin-dependent inflammation in Selp(KI) (/-) mice. Higher basal P-selectin in Selp(KI) (/) (KI) mice compensated for this defect. Therefore, divergent sequences in a short promoter mediate most of the functionally significant differences in expression of human and murine P-selectin in vivo.

Complementary Proteome and Transcriptome Profiling in Developing Grains of a Notched-Belly Rice Mutant Reveals Key Pathways Involved in Chalkiness Formation.

Rice grain chalkiness is a highly complex trait involved in multiple metabolic pathways and controlled by polygenes and growth conditions. To uncover novel aspects of chalkiness formation, we performed an integrated profiling of gene activity in the developing grains of a notched-belly rice mutant. Using exhaustive tandem mass spectrometry-based shotgun proteomics and whole-genome RNA sequencing to generate a nearly complete catalog of expressed mRNAs and proteins, we reliably identified 38,476 transcripts and 3,840 proteins. Comparison between the translucent part and chalky part of the notched-belly grains resulted in only a few differently express genes (240) and differently express proteins (363), thus making it possible to focus on 'core' genes or common pathways. Several novel key pathways were identified as of relevance to chalkiness formation, in particular the shift of C and N metabolism, the down-regulation of ribosomal proteins and the resulting low abundance of storage proteins especially the 13 kDa prolamin subunit, and the suppressed photosynthetic capacity in the pericarp of the chalky part. Further, genes and proteins as transporters for carbohydrates, amino acid/peptides, proteins, lipids and inorganic ions showed an increasing expression pattern in the chalky part of the notched-belly grains. Similarly, transcripts and proteins of receptors for auxin, ABA, ethylene and brassinosteroid were also up-regulated. In summary, this joint analysis of transcript and protein profiles provides a comprehensive reference map of gene activity regarding the physiological state in the chalky endosperm.