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21.
Rueda P Balabanian K Lagane B Staropoli I Chow K Levoye A Laguri C Sadir R Delaunay T Izquierdo E Pablos JL Lendinez E Caruz A Franco D Baleux F Lortat-Jacob H Arenzana-Seisdedos F 《PloS one》2008,3(7):e2543
The CXCL12gamma chemokine arises by alternative splicing from Cxcl12, an essential gene during development. This protein binds CXCR4 and displays an exceptional degree of conservation (99%) in mammals. CXCL12gamma is formed by a protein core shared by all CXCL12 isoforms, extended by a highly cationic carboxy-terminal (C-ter) domain that encompass four overlapped BBXB heparan sulfate (HS)-binding motifs. We hypothesize that this unusual domain could critically determine the biological properties of CXCL12gamma through its interaction to, and regulation by extracellular glycosaminoglycans (GAG) and HS in particular. By both RT-PCR and immunohistochemistry, we mapped the localization of CXCL12gamma both in mouse and human tissues, where it showed discrete differential expression. As an unprecedented feature among chemokines, the secreted CXCL12gamma strongly interacted with cell membrane GAG, thus remaining mostly adsorbed on the plasmatic membrane upon secretion. Affinity chromatography and surface plasmon resonance allowed us to determine for CXCL12gamma one of the higher affinity for HS (K(d) = 0.9 nM) ever reported for a protein. This property relies in the presence of four canonical HS-binding sites located at the C-ter domain but requires the collaboration of a HS-binding site located in the core of the protein. Interestingly, and despite reduced agonist potency on CXCR4, the sustained binding of CXCL12gamma to HS enabled it to promote in vivo intraperitoneal leukocyte accumulation and angiogenesis in matrigel plugs with much higher efficiency than CXCL12alpha. In good agreement, mutant CXCL12gamma chemokines selectively devoid of HS-binding capacity failed to promote in vivo significant cell recruitment. We conclude that CXCL12gamma features unique structural and functional properties among chemokines which rely on the presence of a distinctive C-ter domain. The unsurpassed capacity to bind to HS on the extracellular matrix would make CXCL12gamma the paradigm of haptotactic proteins, which regulate essential homeostatic functions by promoting directional migration and selective tissue homing of cells. 相似文献
22.
Seung Hwan Lee Julius van der Werf Sang Hong Lee Da Jeong Lim Eung Woo Park Cedric Gondro Duhak Yoon Sung Jong Oh Oun Hyun Kim John Gibson John Thompson 《Genes & genomics.》2012,34(1):43-49
Meat quality traits are the most economically important traits affecting the beef industry in Korea. We performed a whole genome quantitative trait locus (QTL) mapping study of carcass data in Hanwoo Korean cattle. Two hundred sixty-six Hanwoo steers from 65 sires were genotyped using a 10K Affymetrix SNP chip. The average SNP interval across the bovine genome was 1.5Mb. Associations between each individual SNP and four carcass traits [carcass weight (CWT), eye muscle area (EMA), back fat thickness (BFT), and marbling (MAR)] were assessed using a linear mixed model of each trait. Combined linkage and linkage disequilibrium analysis (LDLA) detected six potential QTL on BTA04, 06, 13, 16, 17, and 23 at the chromosome-wise level (P<0.05). Two MAR QTL were detected at 52.2 cM of BTA06 and 46.04 cM of BTA17. We identified three genes (ARAP2, LOC539460, and LOC511424) in the QTL region of BTA06 and seven genes (RPS14, SCARB1, LOC782103, BRI3BP, AACS, DHX37, and UBC) in the QTL region of BTA17. One significant QTL for CWT was detected at 100 cM on BTA04 and the corresponding QTL region spanned 1.7 cM from 99.7 to 101.4 cM. For EMA QTL, one significant QTL was detected at 3.9 cM of BTA23 and the most likely QTL interval was 1.4 cM, placing 15 candidate genes in the marker bracket. Finally, two QTL for BFT were identified at 68 cM on BTA13 and 24 cM on BTA16. The LPIN3 gene, which is functionally associated with lipodystrophy in humans, is located in the BFT QTL on BTA13. Thus, two potential candidate genes, acetoacetyl-CoA synthetase (AACS) and lipin (LPIN), were detected in QTL regions on BTA17 for MAR and BTA13 for BFT, respectively. In conclusion, LDLA analysis can be used to detect chromosome regions harboring QTL and candidate genes with a low density SNP panel, yielding relatively narrow confidence intervals regarding location. 相似文献
23.
For studying heart pathologies on the cellular level, cultured adult cardiac myocytes represent an important approach. We aimed to explore a novel adult rat ventricular myocyte culture system with minimised dedifferentiation allowing extended experimental manipulation of the cells such as expression of exogenous proteins. Various culture conditions were investigated including medium supplement, substrate coating and electrical pacing for one week. Adult myocytes were probed for (i) viability, (ii) morphology, (iii) frequency dependence of contractions, (iv) Ca(2+) transients, and (v) their tolerance towards adenovirus-mediated expression of the Ca(2+) sensor "inverse pericam". Conventionally, in either serum supplemented or serum-free medium, myocytes dedifferentiated into flat cells within 3 days or cell physiology and morphology were impaired, respectively. In contrast, myocytes cultured in medium supplemented with an insulin-transferrin-selenite mixture on substrates coated with extracellular matrix proteins showed an increased cell attachment and a conserved cross-striation. Moreover, these myocytes displayed optimised preservation of their contractile behaviour and Ca(2+) signalling even under conditions of continuous electrical pacing. Sustained expression of inverse pericam did not alter myocyte function and allowed long lasting high speed Ca(2+) imaging of electrically driven adult myocytes. Our single-cell model thus provides a new advance for high-content screening of these highly specialised cells. 相似文献
24.
Martin Petrek Cedric Hermans Ví t zslav Kolek Jarmila Fialov Alfred Bernard 《Biomarkers》2002,7(1):58-67
The Clara cell protein (CC16) is a small and readily diffusible protein of 16kDa secreted by bronchiolar Clara cells in the distal airspaces. These epithelial cells are altered in several pulmonary pathological processes induced by various lung toxicants. In the search for a new biomarker of asbestos-induced lung impairment, we used a sensitive immunoassay to determine the levels of CC16 in bronchoalveolar fluid (BALF) and serum of subjects exposed to asbestos compared with a group of healthy controls. In the BALF of asbestos-exposed subjects there was an insignificant trend towards CC16 elevation compared with controls, with a (mean ±SD of 0.81 ±0.65mg l-1 for asbestos-exposed subjects (n = 23) versus 0.39 ±0.19mg l-1 for controls (n = 11) (p = 0.09). In serum, CC16 concentration was significantly increased among asbestos-exposed subjects, with values of 27.2 ±24.0 µg l-1 for asbestos-exposed subjects (n = 34) versus 16.1 ±7.6 µg l-1 for controls (n = 34) (p = 0.01). Regarding the effects of smoking, there were significant differences between generally lower CC16 levels in serum and BALF (p = 0.05 and 0.001, respectively) of smokers compared with the higher levels in non-smokers. Serum CC16 levels positively correlated with those in BALF, which is consistent with a diffusional transfer of CC16 from the bronchoalveolar space into the serum. No association, however, emerged between the levels of CC16 in serum or BALF and either the duration of asbestos exposure or the severity of the lung impairment as assessed by chest X-ray. These findings suggest that exposure to asbestos elicits early changes in the local and, importantly, also the systemic levels of CC16. This pneumoprotein therefore appears as a promising non-invasive biomarker of asbestos-induced lung injury and occupational disease in both smoking and non-smoking exposed subjects. 相似文献
25.
Yoann Anselmetti Wandrille Duchemin Eric Tannier Cedric Chauve Sèverine Bérard 《BMC genomics》2018,19(2):96
Background
Genomes rearrangements carry valuable information for phylogenetic inference or the elucidation of molecular mechanisms of adaptation. However, the detection of genome rearrangements is often hampered by current deficiencies in data and methods: Genomes obtained from short sequence reads have generally very fragmented assemblies, and comparing multiple gene orders generally leads to computationally intractable algorithmic questions.Results
We present a computational method, ADseq, which, by combining ancestral gene order reconstruction, comparative scaffolding and de novo scaffolding methods, overcomes these two caveats. ADseq provides simultaneously improved assemblies and ancestral genomes, with statistical supports on all local features. Compared to previous comparative methods, it runs in polynomial time, it samples solutions in a probabilistic space, and it can handle a significantly larger gene complement from the considered extant genomes, with complex histories including gene duplications and losses. We use ADseq to provide improved assemblies and a genome history made of duplications, losses, gene translocations, rearrangements, of 18 complete Anopheles genomes, including several important malaria vectors. We also provide additional support for a differentiated mode of evolution of the sex chromosome and of the autosomes in these mosquito genomes.Conclusions
We demonstrate the method’s ability to improve extant assemblies accurately through a procedure simulating realistic assembly fragmentation. We study a debated issue regarding the phylogeny of the Gambiae complex group of Anopheles genomes in the light of the evolution of chromosomal rearrangements, suggesting that the phylogenetic signal they carry can differ from the phylogenetic signal carried by gene sequences, more prone to introgression.26.
27.
Giuseppe Donati Marco Campera Michela Balestri Marta Barresi Kristina Kesch Kelard Ndremifidy Jonhy Rabenantoandro Elena Racevska Faly Randriatafika Murielle Ravaolahy Andriamandranto M. Ravoahangy Marika Roma Fiona Rowe Luca Santini Valentina Serra Stacey L. Zander Cedric Tsagnangara Manon Vincelette Jean-Baptiste Ramanamanjato 《American journal of primatology》2020,82(4):e23106
While the drivers of primate persistence in forest fragments have been often considered at the population level, the strategies to persist in these habitats have been little investigated at the individual or group level. Considering the rapid variation of fragment characteristics over time, longitudinal data on primates living in fragmented habitats are necessary to understand the key elements for their persistence. Since translocated animals have to cope with unfamiliar areas and face unknown fluctuations in food abundance, they offer the opportunity to study the factors contributing to successful migration between fragments. Here, we illustrated the evolution of the foraging strategies of translocated collared brown lemurs (Eulemur collaris) over an 18-year period in the Mandena Conservation Zone, south-east Madagascar. Our aim was to explore the ability of these frugivorous lemurs to adjust to recently colonized fragmented forests. Although the lemurs remained mainly frugivorous throughout the study period, over the years we identified a reduction in the consumption of leaves and exotic/pioneer plant species. These adjustments were expected in frugivorous primates living in a degraded area, but we hypothesize that they may also reflect the initial need to cope with an unfamiliar environment after the translocation. Since fragmentation is often associated with the loss of large trees and native vegetation, we suggest that the availability of exotic and/or pioneer plant species can provide an easy-to-access, nonseasonal food resource and be a key factor for persistence during the initial stage of the recolonization. 相似文献
28.
Fang E. He Zhang Wanli Yin Chongyang Wang Yuanli Liu Yanze Li Linlin Wang Yue Wu Runze Zhang Chendan Zou Tianjun Song Cedric Matunda Chaoxia Zou Xu Gao 《Cell death & disease》2022,13(1)
Premature ovarian insufficiency (POI) is a heterogeneous and multifactorial disorder. In recent years, there has been an increasing interest in research on the pathogenesis and treatment of POI, owing to the implementation of the second-child policy in China. Cytoplasmic polyadenylation element-binding protein 3 (CPEB3) is an RNA-binding protein that can bind to specific RNA sequences. CPEB3 can bind to and affect the expression, cellular location, and stability of target RNAs. Cpeb3 is highly expressed in the ovary; however, its functions remain unknown. In this study, Cpeb3-mutant mice were used to characterize the physiological functions of CPEB3. Cpeb3-mutant female mice manifested signs of gradual loss of ovarian follicles, ovarian follicle development arrest, increased follicle atresia, and subfertility with a phenotype analogous to POI in women. Further analysis showed that granulosa cell proliferation was inhibited and apoptosis was markedly increased in Cpeb3-mutant ovaries. In addition, the expression of Gdf9, a potential target of CPEB3, was decreased in Cpeb3-mutant ovaries and oocytes. Altogether, these results reveal that CPEB3 is essential for ovarian follicle development and female fertility as it regulates the expression of Gdf9 in oocytes, disruption of which leads to impaired ovarian follicle development and POI.Subject terms: RNA-binding proteins, Infertility 相似文献
29.
Cedric Shackleton 《Steroids》2009,74(3):288-7370
Definitive proof of anabolic steroid abuse in sports was not possible prior to the introduction of combined gas chromatography/mass spectrometry (GC/MS).This is a report of the early history (1960-1980) of GC/MS and radioimmunoassay, and how these techniques were utilized in the first years of steroid doping control in athletics. There were several key individuals and research groups involved in the early technical developments, and their essential contributions have been acknowledged. Our laboratory was the first IAAF (International Association of Athletic Federations) sanctioned site to do steroid GC/MS steroid analysis resulting in athletes being disqualified from competition. We had notable successes, including the only East German female competitor ever suspended during the tenure of the DDR (Deutsche Demokratische Republik). This paper not only covers scientific advances and milestones in the incorporation of steroid testing into international athletics, but also includes personal anecdotes of these early years before doping control became justifiably regimented. By the early 1980s, in anticipation of the Los Angeles Olympic games, dedicated year-round sports testing facilities had been established and part-time amateurs could step aside. 相似文献
30.
Meritxell Gironella Cedric Malicet Carla Cano Maria José Sandi Tewfik Hamidi Ricardo Martin Neme Tauil Mariela Baston Pia Valaco Silvia Moreno Frederic Lopez Jose Luis Neira Jean Charles Dagorn Juan Lucio Iovanna 《Journal of cellular physiology》2009,221(3):594-602
The stress protein p8 is a small, highly basic, unfolded, and multifunctional protein. We have previously shown that most of its functions are exerted through interactions with other proteins, whose activities are thereby enhanced or repressed. In this work we describe another example of such mechanism, by which p8 binds and negatively regulates MSL1, a histone acetyl transferase (HAT)‐associated protein, which in turn binds the DNA‐damage‐associated 53BP1 protein to facilitate DNA repair following DNA γ‐irradiation. Contrary to the HAT‐associated activity, MSL1‐dependent DNA‐repair activity is almost completely dependent on 53BP1 expression. The picture that has emerged from our findings is that 53BP1 could be a scaffold that gets the HAT MSL1‐dependent DNA‐repair activity to the sites of DNA damage. Finally, we also found that, although p8 expression is transiently activated after γ‐irradiation, it is eventually submitted to sustained down‐regulation, presumably to allow development of MSL1‐associated DNA‐repair activity. We conclude that interaction of MSL1 with 53BP1 brings MSL1‐dependent HAT activity to the vicinity of damaged DNA. MSL1‐dependent HAT activity, which is negatively regulated by the stress protein p8, induces chromatin remodeling and relaxation allowing access to DNA of the repair machinery. J. Cell. Physiol. 221: 594–602, 2009. © 2009 Wiley‐Liss, Inc. 相似文献