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Floating-Harbor syndrome (FHS) is a rare genetic disease affecting human development caused by heterozygous truncating mutations in theSrcapgene, which encodes the ATPase SRCAP, the core catalytic subunit of the homonymous chromatin-remodeling complex. Using a combined approach, we studied the involvement of SRCAP protein in cell cycle progression in HeLa cells. In addition to the canonical localization in interphase nuclei, both SRCAP and itsDrosophilaorthologue DOMINO-A localized to the mitotic apparatus after nuclear envelope breakdown. Moreover, SRCAP and DOMINO-A depletion impaired mitosis and cytokinesis in human and Drosophila cells, respectively. Importantly, SRCAP interacted with several cytokinesis regulators at telophase, strongly supporting a direct role in cytokinesis, independent of its chromatin remodeling functions. Our results provide clues about previously undetected, evolutionarily conserved roles of SRCAP in ensuring proper mitosis and cytokinesis. We propose that perturbations in cell division contribute to the onset of developmental defects characteristic of FHS.SummarySignificance statementSrcapis the causative gene of the rare Floating Harbor syndrome (FHS). It encodes the ATPase SRCAP, the core catalytic subunit of the homonymous multiprotein chromatin-remodeling complex in humans, which promotes the exchange of canonical histone H2A with the H2A.Z variant. According to the current view on SRCAP protein functions, FHS is caused by chromatin remodeling defects. Our findings suggest that, in addition to the established function as epigenetic regulator, SRCAP plays previously undetected and evolutionarily conserved roles in cell division. Hence, we propose that perturbations in cell division produced by SRCAP mutations are important causative factors co-occurring at the onset of FHS.

Up-regulation of the dystrophin-related gene utrophin represents a promising therapeutic strategy for the treatment of Duchenne muscular dystrophy (DMD). The strategy is based on the capacity of utrophin to functionally replace defective dystrophin. In order to re-program the utrophin expression level in muscle, we engineered artificial zinc finger transcription factors (ZFATFs) on Zif268/Egr1 backbone. Using selective amino acid substitutions, the natural Zif268 transcription factor was specifically re-directed to the human and mouse conserved regions of the utrophin promoter ''A''. Furthermore, these minimally modified ZF-ATFs were designed to minimize any host immune-response against these proteins. Our present focus is the delivery of ZFATFs using recombinant Adeno-associated viral vectors engineered to express the therapeutic genes under the control of the human alpha-actin muscle specific promoter (mAAV-vector), combined with the use of the muscle-targeting AAV-serotype 8. Upon intraperitoneal injection of mAAV8- ZF-ATFs into dystrophin-deficient (mdx) mice, a significant amelioration of the pathological phenotype was observed. Histological and physiological analysis revealed a reduction of fiber necrosis and cell infiltration, as well as the functional recovery in muscle contractile force. Since utrophin is also a key determinant of the neuromuscular junction (NMJ), ongoing studies will characterize the NMJ in mAAV8-ZF-ATF treated mice. In summary, the development of ZF-ATF-re-directed technology, coupled with the mAAV delivery, highlights the potential of this novel therapeutic strategy for treatment of DMD.

A methanolic extract and two fractions (n-hexane and ethyl acetate) from Virola oleifera leaves and some compounds (one lignan and two flavonoids) were investigated to verify the analgesic activity by using the writhing test in mice. The crude methanolic extract showed a moderate analgesic effect (about 40% of inhibition in this test at 10 mg/kg), whereas n-hexane and ethyl acetate fractions caused inhibition of 51.3 ± 5.9% and 50.5 ± 6.3% , respectively. Oleiferin-C (1), a lignan isolated from the n-hexane fraction, showed an interesting analgesic potential in this model when compared to two standard drugs, paracetamol (4-acetamidophenol) and aspirin (acetylsalicylic acid). The ID50 calculated for this compound was 17.25 μmol/kg, with confidence interval between 13.7 and 21.3 μmol/kg, being about 8 times more potent than the standard drugs. The mixture of two glycoside-flavonoids, identified as astilbin (2) and quercitrin (3), also exhibited good analgesic activity, causing 63% of reduction of abdominal constriction in mice. These results suggest beneficial effect of this plant to treat dolorous processes.

As part of the program of our research group to search for new and effective substances from the Brazilian biodiversity, the present work evaluates the antibacterial activity of four species from the Brazilian flora ( Garcinia achachairu, Macrosiphonia velame, Rubus niveus and Pilea microphylla) against Bacillus subtilis, Staphylococcus aureus and S. saprophyticus (Gram-positive bacteria), Escherichia coli (Gram-negative bacterium) and Candida albicans (yeast). The extracts of R. niveus and M. velame showed promising antibacterial activity with MICs, ranging from 1000 to 125 μg/mL. Bio-guided fractionation of M. velame yielded four compounds, with the highest inhibition being observed for compound 3, with a MIC of 125 μg/mL against S. aureus. The combinations of fractions 2 and 4 showed beneficial effect against Gram-positive bacteria (additive effect), suggesting a possible synergistic effect.

This study was carried out to determine the effect of 15 different natural and synthetic chalcones on the proliferation of both established and primary ovarian cancer cells expressing type II oestrogen binding sites (type II EBS). The binding affinity of chalcones for type II EBS was also tested. At concentrations from 0.1 to 10 microM, chalcones inhibited ovarian cancer cell proliferation and [3H]oestradiol ([3H]E2) binding to type II EBS. Considering the structure-related variation in IC50 (concentration resulting in a 50% inhibition of cell growth) and Di50 (concentration resulting in a 50% displacement of [3H]E2 bound to type II EBS), it appeared that the presence of an alpha-beta double bond, the hydroxylation in 3 or 2 of ring B and the absence of a prenyl group were important to both the antiproliferative and binding activity. Structure-related variations in IC50 and Di50 were significantly concordant (Fisher's exact test: P = 0.0291), suggesting that there may be a type II EBS-mediated mechanism for chalcone antiproliferative activity. Our data indicate that chalcones could be considered as potential new anticancer drugs.

From the stems of Croton micans Sw., five new 3,4- seco-ent-kaurene dimers: micansinoic acid (1), isomicansinoic acid (2), and the dimethyl (3), monomethyl (4) and monoethyl ester (5) of micansinoic acid were isolated. The structures of the new compounds were elucidated by spectroscopic data interpretation, mainly 1D and 2D NMR experiments and MS. These compounds are the first 3,4- seco-ent-kaurene dimers from a Croton species.