Thyroid hormone effects on diferential expression of rat heart genes.

No coração, doses elevadas de hormônio tireoideano (T3) por tempo prolongado promove hipertrofia cardíaca. Os mecanismos envolvidos neste processo necessitam de maior esclarecimento. Analisou-se dados de um ensaio de microarray de tecido cardíaco de ratos submetidos a hipertireoidismo experimental. O algoritmo MAS5 foi mais eficiente para processamento dos dados. Identificou-se os filamentos grossos, banda M e discos intercalares como hotspots de atuação do T3. A T-Caderina apresentou aumento transitório nos níveis de mRNA e proteicos sob efeito do T3. Estudo de imunofluorescência evidenciou marcação para T-Caderina próxima à membrana plasmática de cardiomiócitos. Com 24 horas de tratamento com T3, observamos aumento global e difuso de marcação para T-Caderina. Obeservou-se marcação nuclear para T-Caderina. Portanto, é possível que a T-caderina possa estar envolvida no processo de hipertrofia cardíaca. Todavia, para verificar essa possibilidade, são necessários mais estudos.Cardiac hypertrophy is observed in response to long-term hyperthyroidism. The molecular basis of cardiac hypertrophy induced by hyperthyroidism remains to be determined. Using microarray approach, the gene expression profile of heart tissue from rats submitted to hyperthyroidism were analysed. MAS5 were found to be the best for our low-level analysis. Sarcomeric hotspots such as thick-filaments, M-band and intercalated disks under thyroid hormone (T3) treatment were identified. T3 induced transient mRNA and protein levels of T-Cadherin, a interecalated disks member. T-Cadherin were observed next to plasmatic membrane on immunofluorescence analysis. On 24 hours group, diffuse cytoplasmic T-Cadherin staining were evident. Another interesting aspect was T-Cadherin nuclear staining in all groups. Moreover, T-Cadherin possibly play role in T3-induced cardiac hypertrophy. However further studies are needed to verify this possibility

Global changes in nitration levels and DNA binding profile of Trypanosoma cruzi histones induced by incubation with host extracellular matrix.

Adhesion of T. cruzi trypomastigotes to components of the extracellular matrix (ECM) is an important step in mammalian host cell invasion. We have recently described a significant increase in the tyrosine nitration levels of histones H2A and H4 when trypomastigotes are incubated with components of the ECM. In this work, we used chromatin immunoprecipitation (ChIP) with an anti-nitrotyrosine antibody followed by mass spectrometry to identify nitrated DNA binding proteins in T. cruzi and to detect alterations in nitration levels induced upon parasite incubation with the ECM. Histone H1, H2B, H2A and H3 were detected among the 9 most abundant nitrated DNA binding proteins using this proteomic approach. One nitrated tyrosine residue (Y29) was identified in Histone H2B in the MS/MS spectrum. In addition, we observed a significant increase in the nitration levels of histones H1, H2B, H2A and H4 upon parasite incubation with ECM. Finally, we used ChIP-Seq to map global changes in the DNA binding profile of nitrated proteins. We observed a significant change in the binding pattern of nitrated proteins to DNA after parasite incubation with ECM. This work provides the first global profile of nitrated DNA binding proteins in T. cruzi and additional evidence for modification in the nitration profile of histones upon parasite incubation with ECM. Our data also indicate that the parasite interaction with the ECM induces alterations in chromatin structure, possibly affecting nuclear functions

PlanMine 3.0-improvements to a mineable resource of flatworm biology and biodiversity.

Flatworms (Platyhelminthes) are a basally branching phylum that harbours a wealth of fascinating biology, including planarians with their astonishing regenerative abilities and the parasitic tape worms and blood flukes that exert a massive impact on human health. PlanMine (http://planmine.mpi-cbg.de/) has the mission objective of providing both a mineable sequence repository for planarians and also a resource for the comparative analysis of flatworm biology. While the original PlanMine release was entirely based on transcriptomes, the current release transitions to a more genomic perspective. Building on the recent availability of a high quality genome assembly of the planarian model species Schmidtea mediterranea, we provide a gene prediction set that now assign existing transcripts to defined genomic coordinates. The addition of recent single cell and bulk RNA-seq datasets greatly expands the available gene expression information. Further, we add transcriptomes from a broad range of other flatworms and provide a phylogeny-aware interface that makes evolutionary species comparisons accessible to non-experts. At its core, PlanMine continues to utilize the powerful InterMine framework and consistent data annotations to enable meaningful inter-species comparisons. Overall, PlanMine 3.0 thus provides a host of new features that makes the fascinating biology of flatworms accessible to the wider research community