Annexin-A1 gene expression during liver development and post-translation modification after experimental endotoxemia

Objective and design: We have previously reported a role for annexin-A1 in liver proliferation and tumorogenicity as well as its action as an acute phase protein in a model of endotoxemia in interleukin-6 null mice.Material and methods: In this study, we have investigated the analysis of the gene and protein expression in annexin-A1 null mice and the wild type livers during foetal and adult life, and in the presence of a proinflammatory stimulus.Results: The data indicate a link between the expression of the annexin-A1 as serine-phosphorylated-protein during early events of the inflammatory response and as tyrosine-phosphorylated-form at later time-points, during the resolution of inflammation.Conclusions: The study of annexin-A1 post-translation modification may promote a new annexin-A1 peptide discovery programme to treat specific pathologies.

Progesterone (PR), Oestrogen (ER-alpha and ER-beta) and Oxytocin (OTR) Gene Expression in the Oviduct and Uterus of Pregnant and Non-pregnant Bitches

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Analysis of the Nicotiana tabacum Stigma/Style Transcriptome Reveals Gene Expression Differences between Wet and Dry Stigma Species

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Variation of genetic expression during development, revealed by esterase patterns in Aedes aegypti (Diptera, Culicidae)

Polyacrylamide gel electrophoresis was used to analyze esterase patterns during development of Aedes aegypti from the cities of Marília and São José do Rio Preto (SJRP), Brazil. The zymograms showed a total of 23 esterase bands, 22 of which were in the specimens from Marília and 19 in those from SJRP. These esterase bands were considered to be the product of 23 alleles distributed tentatively in eight genetic loci. Most of the alleles were developmentally regulated. The larval stage expressed the greatest number of them (19 alleles, from the eight loci, in Marília; and 17 alleles, from seven loci, in SJRP). The pupal stage expressed 10 alleles from seven loci, in both populations, and the adult stage expressed 8 alleles from five and six loci in SJRP and Marília, respectively. Some alleles that were active in every stage were developmentally controlled at the level of expression (amount of product). A single allele was constitutively and highly expressed, in larvae, pupae, and adults, in both populations. Differences in esterase synthesis among stages are probably due to regulatory mechanisms acting in agreement with the requirements of a variable number of processes in which esterases are involved. The larval stage is the most active in developmental processes and shows very intense intake of food and very high mobility. These features may demand increased esterase production at that stage. Comparison of the two populations examined showed (besides the existence of alleles that they do not share) that they exhibit differences in the control of expression of other alleles. Such findings may reflect genetic differences between founders in each population, but the possibility of involvement of the intensive use of insecticides in SJRP is also discussed.

p38 MAPK regulates IL-1β induced IL-6 expression through mRNA stability in osteoblasts

Osteoblast-derived IL-6 functions in coupled bone turnover by supporting osteoclastogenesis favoring bone resorption instead of bone deposition. Gene regulation of IL-6 is complex occurring both at transcription and post-transcription levels. The focus of this paper is at the level of mRNA stability, which is important in IL-6 gene regulation. Using the MC3T3-E1 as an osteoblastic model, IL-6 secretion was dose dependently decreased by SB203580, a p38 MAPK inhibitor. Steady state IL-6 mRNA was decreased with SB203580 (2 μM) ca. 85% when stimulated by IL-1β (1-5 ng/ ml). These effects require de novo protein synthesis as they were inhibited by cycloheximide. p38 MAPK had minor effects on proximal IL-6 promoter activity in reporter gene assays. A more significant effect on IL-6 mRNA stability was observed in the presence of SB203580. Western blot analysis confirmed that SB203580 inhibited p38 MAP kinase, in response to IL-1β in a dose dependent manner in MC3T3-E1 cells. Stably transfected MC3T3-E1 reporter cell lines (MC6) containing green fluorescent protein (GFP) with the 3′untranslated region of IL-6 were constructed. Results indicated that IL-1β, TNFα, LPS but not parathyroid hormone (PTH) could increase GFP expression of these reporter cell lines. Endogenous IL-6 and reporter gene eGFP-IL-6 3′UTR mRNA was regulated by p38 in MC6 cells. In addition, transient transfection of IL-6 3′UTR reporter cells with immediate upstream MAP kinase kinase-3 and -6 increased GFP expression compared to mock transfected controls. These results indicate that p38 MAPK regulates IL-1β-stimulated IL-6 at a post transcriptional mechanism and one of the primary targets of IL-6 gene regulation is the 3′UTR of IL-6.