Declines in individuals' growth in exploited fish species are generally attributed to evolutionary consequences of size-selective fishing or to plastic responses due to constraints set by changing environmental conditions dampening individuals' growth. However, other processes such as growth compensation and non-directional selection can occur and their importance on the overall phenotypic response of exploited populations has largely been ignored. Using otolith growth data collected in European anchovy and sardine of the Bay of Biscay (18 cohorts from 2000 to 2018), we parameterized the breeder's equation to determine whether declines in size-at-age in these species were due to an adaptive response (i.
View Article and Find Full Text PDFFar-red and near-infrared (NIR) absorbing/emitting dyes have found diverse applications in biomedicine and material science. However, the absorption and emission of classical BODIPY chromophores at short wavelength hamper their applications. Several strategies have been adopted to modify the structure of the BODIPY core to design NIR dyes.
View Article and Find Full Text PDFNuclear Inhibitor of PP1 (NIPP1) is a conserved regulatory subunit of protein phosphatase PP1. The selective deletion of NIPP1 in mouse liver parenchymal cells or skin epidermal cells culminates in a late-onset hyperproliferation of a subset of resident progenitor cells. Although a hyperplastic phenotype is usually tumor promoting, we show here that the absence of NIPP1 conferred a strong resistance to chemically induced hepatocellular or skin carcinoma.
View Article and Find Full Text PDFNuclear inhibitor of protein phosphatase 1 (NIPP1) is a ubiquitously expressed nuclear protein that regulates functions of protein serine/threonine phosphatase-1 in cell proliferation and lineage specification. The role of NIPP1 in tissue homeostasis is not fully understood. This study shows that the selective deletion of NIPP1 in mouse epidermis resulted in epidermal hyperproliferation, a reduced adherence of basal keratinocytes, and a gradual decrease in the stemness of hair follicle stem cells, culminating in hair loss.
View Article and Find Full Text PDFA metal-free C-H formylation and acylation of BODIPY dyes using a variety of dioxolane derivatives as aldehyde equivalents is reported, providing a postfunctionalization method for controllable synthesis of BODIPYs with carbonyl groups at 3,5-positions via a radical process. The photophysical properties of resultant dyes from this efficient one-pot, chemo- and site-selective transformation have been studied.
View Article and Find Full Text PDFUnderstanding the nature and origins of food sources supporting coastal lagoon-inhabiting organisms is necessary to evaluate the ecological status of such ecosystems. The trophic ecology of a bivalve species Spondylus crassisquama was studied in the Ojo de Liebre lagoon (Baja California, Mexico), combining stable isotope (SI), fatty acid (FA) and sterol analyses along a transect under oceanic influences. The second objective of the study was to investigate if sterol compositions give complementary information to those obtained from FA and SI.
View Article and Find Full Text PDFAn oxidative cross-dehydrogenative coupling of BODIPYs with toluene and its derivatives has been developed, allowing for the facile synthesis of a broad range of structurally diverse α-benzylated BODIPYs. The method exhibits excellent chemoselectivity, affording exclusively α-benzylated BODIPYs in the presence of t-BuOOH and a catalytic amount of Cu(OAc). The direct use of readily available toluene and its derivatives as coupling partners avoids unproductive steps for preactivating the functional group installation, and is therefore attractive.
View Article and Find Full Text PDFDespite great interest and decades of research, the musculoskeletal relationships of the masticatory system in primates are still not fully understood. However, without a clear understanding of the interplay between muscles and bones it remains difficult to understand the functional significance of morphological traits of the skeleton. Here, we aim to study the impacts of the masticatory muscles on the shape of the cranium and the mandible as well as their co-variation in strepsirrhine primates.
View Article and Find Full Text PDFNIPP1 is one of the major nuclear interactors of protein phosphatase PP1. The deletion of NIPP1 in mice is early embryonic lethal, which has precluded functional studies in adult tissues. Hence, we have generated an inducible NIPP1 knockout model using a tamoxifen-inducible Cre recombinase transgene.
View Article and Find Full Text PDFA BuNI/tBuOOH-catalyzed, highly regioselective cross-dehydrogenative coupling (CDC) of the α-C-H bond(s) of the BODIPY core has been developed. The α-regioselective alkylation reaction utilizes easily accessible coupling partners, namely commercial allylic alkenes and ethers - even common, inert organic solvents, such as tetrahydrofuran, diethyl ether and 1,4-dioxane. The high α-regioselectivity of this CDC reaction is attributable to the radical process involved and provides a facile access to a variety of α-functionalized BODIPYs, which are hard to access through current synthetic methods.
View Article and Find Full Text PDFThe Ppp1r8 gene encodes NIPP1, a nuclear interactor of protein phosphatase PP1. The deletion of NIPP1 is embryonic lethal at the gastrulation stage, which has hampered its functional characterization in adult tissues. Here, we describe the effects of a conditional deletion of NIPP1 in mouse liver epithelial cells.
View Article and Find Full Text PDFThe generality of the palladium-catalyzed C-C coupling Negishi reaction when applied to haloBODIPYs is demonstrated on the basis of selected starting BODIPYs, including polyhalogenated and/or asymmetrical systems, and organozinc reagents. This reaction is an interesting synthetic tool in BODIPY chemistry, mainly because it allows a valuable regioselective postfunctionalization of BODIPY chromophores with different functional groups. In this way, functional patterns that are difficult to obtain by other procedures (e.
View Article and Find Full Text PDFHere we describe a new BODIPY-based membrane probe (1) that provides an alternative to dialkylcarbocyanine dyes, such as DiI-C18, that can be excited in the blue spectral region. Compound 1 has unbranched octadecyl chains at the 3,5-positions and a meso-amino function. In organic solvents, the absorption and emission maxima of 1 are determined mainly by solvent acidity and dipolarity.
View Article and Find Full Text PDFThe serine/threonine protein phosphatase-1 (PP1) complex is a key regulator of the cell cycle. However, the redundancy of PP1 isoforms and the lack of specific inhibitors have hampered studies on the global role of PP1 in cell cycle progression in vertebrates. Here, we show that the overexpression of nuclear inhibitor of PP1 (NIPP1; also known as PPP1R8) in HeLa cells culminated in a prometaphase arrest, associated with severe spindle-formation and chromosome-congression defects.
View Article and Find Full Text PDFMaternal embryonic leucine zipper kinase (MELK), a serine/threonine protein kinase, has oncogenic properties and is overexpressed in many cancer cells. The oncogenic function of MELK is attributed to its capacity to disable critical cell-cycle checkpoints and reduce replication stress. Most functional studies have relied on the use of siRNA/shRNA-mediated gene silencing.
View Article and Find Full Text PDFNucleosides Nucleotides Nucleic Acids
June 2016
This paper describes the synthesis of new click-generated nitrogen mustards and their biological evaluation. By using the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction, we managed to synthesize eight new nitrogen mustards. This strategy paves the way for the synthesis of a new family of nitrogen mustard, with an important structural variability.
View Article and Find Full Text PDFProtein phosphatase-1 (PP1) is a key regulator of transcription and is targeted to promoter regions via associated proteins. However, the chromatin binding sites of PP1 have never been studied in a systematic and genome-wide manner. Methylation-based DamID profiling in HeLa cells has enabled us to map hundreds of promoter binding sites of PP1 and three of its major nuclear interactors, i.
View Article and Find Full Text PDFThe deletion of the protein phosphatase-1 (PP1) regulator known as Nuclear Inhibitor of PP1 (NIPP1) is embryonic lethal during gastrulation, hinting at a key role of PP1-NIPP1 in lineage specification. Consistent with this notion we show here that a mild, stable overexpression of NIPP1 in HeLa cells caused a massive induction of genes of the mesenchymal lineage, in particular smooth/cardiac-muscle and matrix markers. This reprogramming was associated with the formation of actin-based stress fibers and retracting filopodia, and a reduced proliferation potential.
View Article and Find Full Text PDFWe describe herein the first radical C-H arylation of BODIPY dyes. This novel, general, one-step synthetic procedure uses ferrocene to generate aryl radical species from aryldiazonium salts and allows the straightforward synthesis of brightly fluorescent (Φ>0.85) 3,5-diarylated and 3-monoarylated boron dipyrrins in up to 86 % yield for a broad range of aryl substituents.
View Article and Find Full Text PDFThe UV-vis electronic absorption and fluorescence emission properties of 8-halogenated (Cl, Br, I) difluoroboron dipyrrin (or 8-haloBODIPY) dyes and their 8-(C, N, O, S) substituted analogues are reported. The nature of the meso-substituent has a significant influence on the spectral band positions, the fluorescence quantum yields, and lifetimes. As a function of the solvent, the spectral maxima of all the investigated dyes are located within a limited wavelength range.
View Article and Find Full Text PDFPhotochem Photobiol Sci
February 2014
The deterministic identifiability analysis of photophysical models for the kinetics of excited-state processes, assuming errorless time-resolved fluorescence data, can verify whether the model parameters can be determined unambiguously. In this work, we have investigated the identifiability of several uncommon models for time-resolved fluorescence with underlying distributions of rate constants which lead to non-exponential decays. The mathematical functions used here for the description of non-exponential fluorescence decays are the stretched exponential or Kohlrausch function, the Becquerel function, the Förster type energy transfer function, decay functions associated with exponential, Gaussian and uniform distributions of rate constants, a decay function with extreme sub-exponential behavior, the Mittag-Leffler function and Heaviside's function.
View Article and Find Full Text PDFProtein phosphatase-1 (PP1) is an essential enzyme for every eukaryotic cell and catalyzes more than half of all protein dephosphorylations at serine and threonine residues. The free catalytic subunit of PP1 shows little substrate selectivity but is tightly regulated in vivo by a large variety of structurally unrelated PP1-interacting proteins (PIPs). PIPs form highly specific dimeric or trimeric PP1 holoenzymes by acting as substrates, inhibitors, and/or substrate-specifiers.
View Article and Find Full Text PDFNucleosides Nucleotides Nucleic Acids
August 2013
This paper deals with the synthesis of nitrogen mustard analogs, derivatives of purine bases. Alkylation in position N-9 and diethanolamine fixation on position 6 were managed by microwave irradiations. Chlorination of these dihydroxylated intermediates led to a cyclization, giving tricyclic purine base analogs bearing a chloroethyl chain.
View Article and Find Full Text PDFThe steady-state, UV-vis electronic absorption and fluorescence emission properties of a large set of 3-aryl and 3,5-diaryl substituted difluoroboron dipyrromethene dyes obtained via direct, palladium-catalyzed C-H (het)arylation of the BODIPY core are reported. The spectra display the narrow absorption and fluorescence emission bands and the generally quite small Stokes shifts characteristic of classic difluoroboron dipyrrins. As a function of the solvent, the spectral maxima are located within a very narrow wavelength range and are slightly red-shifted with increasing solvent polarizability, which is shown to be the crucial parameter influencing the wavelength position of the maxima.
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