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101.
Francesca Chiarini Francesca Paganelli Tommaso Balestra Cristina Capanni Antonietta Fazio Maria Cristina Manara Lorena Landuzzi Stefania Petrini Camilla Evangelisti Pier-Luigi Lollini Alberto M. Martelli Giovanna Lattanzi Katia Scotlandi 《Cell death & disease》2022,13(4)
Lamin A, a main constituent of the nuclear lamina, is involved in mechanosignaling and cell migration through dynamic interactions with the LINC complex, formed by the nuclear envelope proteins SUN1, SUN2 and the nesprins. Here, we investigated lamin A role in Ewing Sarcoma (EWS), an aggressive bone tumor affecting children and young adults. In patients affected by EWS, we found a significant inverse correlation between LMNA gene expression and tumor aggressiveness. Accordingly, in experimental in vitro models, low lamin A expression correlated with enhanced cell migration and invasiveness and, in vivo, with an increased metastatic load. At the molecular level, this condition was linked to altered expression and anchorage of nuclear envelope proteins and increased nuclear retention of YAP/TAZ, a mechanosignaling effector. Conversely, overexpression of lamin A rescued LINC complex organization, thus reducing YAP/TAZ nuclear recruitment and preventing cell invasiveness. These effects were also obtained through modulation of lamin A maturation by a statin-based pharmacological treatment that further elicited a more differentiated phenotype in EWS cells. These results demonstrate that drugs inducing nuclear envelope remodeling could be exploited to improve therapeutic strategies for EWS.Subject terms: Nuclear organization, Cancer 相似文献
102.
Daniela Accili Maura Menghi Giovanni Materazzi Giovanna Menghi 《The Histochemical journal》2001,33(6):363-371
Sialoglycoconjugates in rat sublingual gland acinar cells, at different stages of pre- and post-natal development, were investigated in situ with specific lectins and by the selective removal of terminal sialic acids. Cleavage of acetyl substituents sited in the pyranose ring and/or polyhydroxyl side chain was used as an additional means of characterising the glycoconjugates. The first expression of terminal sialic acid linked to -galactose was found at gestational day 17 and progressive different derivatives were observed. The terminal disaccharide sialic acid-N-acetylgalactosamine was constantly visualized in the sublingual gland from gestational day 18. In both terminal disaccharides, sialic acids were characterized by variable degrees of acetylation and were found to be highly packaged and responsible for the hydration coat. The complex data obtained indicated that the sublingual gland is characterized by a marked fluctuation of complex sialoglycoconjugates that differ from those in the submandibular gland of the same species. 相似文献
103.
Frugis G Giannino D Mele G Nicolodi C Chiappetta A Bitonti MB Innocenti AM Dewitte W Van Onckelen H Mariotti D 《Plant physiology》2001,126(4):1370-1380
Leaves are specialized organs characterized by defined developmental destiny and determinate growth. The overexpression of Knotted1-like homeobox genes in different species has been shown to alter leaf shape and development, but a definite role for this class of genes remains to be established. Transgenics that overexpress Knotted1-like genes present some traits that are characteristic of altered cytokinin physiology. Here we show that lettuce (Lactuca sativa) leaves that overexpress KNAT1, an Arabidopsis kn1-like gene, acquire characteristics of indeterminate growth typical of the shoot and that this cell fate change is associated with the accumulation of specific types of cytokinins. The possibility that the phenotypic effects of KNAT1 overexpression may arise primarily from the modulation of local ratios of different cytokinins is discussed. 相似文献
104.
Giovanna De Matteis Enzo Agostinelli Bruno Mondovì L. Morpurgo 《Journal of biological inorganic chemistry》1999,4(3):348-353
Bovine serum amine oxidase (BSAO) reacts with 2-hydrazinopyridine, which binds the organic cofactor 2,4,5-trihydroxyphenylalanine
quinone, forming a band at 435 nm. The band shifts to 526 nm around 60 °C, to 415 nm upon denaturation, but only shifts to
429 nm upon Cu2+ depletion. Its wavelength and intensity suggest that the adduct has the azo conformation, whilst the same adduct of crystallineEscherichia coli amine oxidase (ECAO) shows the hydrazone conformation in the X-ray structure. The steady state kinetics of aminomethyl- and
aminoethylpyridines confirm that the formation of the product Schiff base, analogous to the azo form of the 2-hydrazinopyridine
adduct, is not hindered in solution. The structural stability of the adduct in the absence of Cu2+ is taken to imply hydrogen bonding of the pyridyl nitrogen to a conserved aspartate, as in the ECAO adduct. Thus the ECAO
adduct provides a good model for a transient intermediate leading to formation of the BSAO azo adduct. On the basis of this
model and of the catalytic competence of Co2+-substituted BSAO, confirmed by the present data, a catalytic reaction scheme is proposed.
Received: 2 December 1998 / Accepted: 22 March 1999 相似文献
105.
B. Yassine-Diab P. Carmichael Fatima-Ezzahra L'Faqihi Giovanna Lombardi Sarah Deacock Claude de Préval Hélène Coppin R. I. Lechler 《Immunogenetics》1999,49(6):532-540
A comprehensive analysis was carried out of the tri-molecular complex of peptide, major histocompatibility class II molecule,
and T-cell receptor (TcR) involved in the recognition of the promiscuous HA (306–318) peptide, restricted by one of two closely
related HLA-DR alleles, HLA-DRB1*0101 and HLA-DRB1*0103. These two DR molecules differ by only three amino acids at positions 67, 70, and 71, in the third variable region of the
DRB1 chain. None of the HA (306–318)-specific T-cell clones restricted by these two DR molecules tolerated amino acid substitution
at the peptide-binding position 71, despite the fact that the substitution did not interfere with peptide binding. The majority
of the DRB1*0103-restricted clones tolerated substitution of the amino acid at the TcR-contacting position 70, while the DRB1*0101-restricted
T cells did not. Biased usage of TRVA and TRVB segments was observed for the DRB1*0103-restricted clones; in contrast, apparently
random usage was seen in the DRB1*0101-restricted T cells. Finally, limiting dilution analysis revealed a lower frequency
of T cells reactive with the HA peptide in a DRB1*0103 compared with a DRB1*0101 individual. Taken together these data suggest
that biased TcR gene usage may reflect a relatively low precursor frequency of T cells, and the need for clonal expansion of a limited set
of high avidity T cells.
Received: 7 August 1998 / Revised: 19 November 1998 相似文献
106.
Semprini S Capon F Bovolenta S Bruscia E Pizzuti A Fabrizi G Schietroma C Zambruno G Dallapiccola B Novelli G 《Human genetics》1999,104(2):130-134
107.
PTX3 plays a key role in the organization of the cumulus oophorus extracellular matrix and in in vivo fertilization 总被引:9,自引:0,他引:9
Salustri A Garlanda C Hirsch E De Acetis M Maccagno A Bottazzi B Doni A Bastone A Mantovani G Beck Peccoz P Salvatori G Mahoney DJ Day AJ Siracusa G Romani L Mantovani A 《Development (Cambridge, England)》2004,131(7):1577-1586
PTX3 is a prototypic long pentraxin that plays a non-redundant role in innate immunity against selected pathogens and in female fertility. Here, we report that the infertility of Ptx3(-/-) mice is associated with severe abnormalities of the cumulus oophorus and failure of in vivo, but not in vitro, oocyte fertilization. PTX3 is produced by mouse cumulus cells during cumulus expansion and localizes in the matrix. PTX3 is expressed in the human cumulus oophorus as well. Cumuli from Ptx3(-/-) mice synthesize normal amounts of hyaluronan (HA), but are unable to organize it in a stable matrix. Exogenous PTX3 restores a normal cumulus phenotype. Incorporation in the matrix of inter-alpha-trypsin inhibitor is normal in Ptx3(-/-) cumuli. PTX3 does not interact directly with HA, but it binds the cumulus matrix hyaladherin tumor necrosis factor alpha-induced protein 6 (TNFAIP6, also known as TSG6) and thereby may form multimolecular complexes that can cross-link HA chains. Thus, PTX3 is a structural constituent of the cumulus oophorus extracellular matrix essential for female fertility. 相似文献
108.
109.
Caretto S Bray Speth E Fachechi C Gala R Zacheo G Giovinazzo G 《Plant cell reports》2004,23(3):174-179
The most biologically active component of vitamin E, -tocopherol, is synthesized in its most effective stereoisomeric form only by photosynthetic organisms. Using sunflower cell cultures, a suitable in vitro production system of natural -tocopherol was established. The most efficient medium was found to be MS basal medium with naphthaleneacetic acid and 6-benzylaminopurine with the addition of casaminoacids and myo-inositol. Culture feeding experiments using biosynthetic precursors showed that -tocopherol production improved by 30% when homogentisic acid was used. Interestingly, time-course experiments with sunflower suspension cultures showed a possible increase of 78% in -tocopherol production when using cultures of longer subculture intervals. Compared to the starting plant tissue, an overall 100% increase of -tocopherol was reached by these sunflower cell cultures. 相似文献
110.
Romagnoli R Baraldi PG Pavani MG Tabrizi MA Moorman AR Di Virgilio F Cattabriga E Pancaldi C Gessi S Borea PA 《Bioorganic & medicinal chemistry letters》2004,14(22):5709-5712
The design, synthesis, and preliminary biological evaluation of the first potent radioligand antagonist for the P2X(7) receptor, named [(3)H]-1-[(S)-N,O-bis-(isoquinolinesulfonyl)-N-methyl-tyrosyl]-4-(o-tolyl)-piperazine (compound 13), are reported. This compound bound to human P2X(7) receptors expressed in HEK transfected cells with K(D) and B(max) value of 3.46+/-0.1 nM and 727+/-73 fmol/mg of protein, respectively. The high affinity and facile labeling makes it a promising radioligand for a further characterization of P2X(7) receptor subtype. 相似文献