Understanding the genetic control of gametogenesis is a central goal of developmental biology and is important for treating infertility in humans. An approach to identifying critical genes in mammals is to search for and study homologues of genes known to play key roles in other organisms. In the fly, Drosophila melanogaster, GUS protein is a component of nuage, an electron-dense aggregation in early germ cells, and is required for oocyte development. GUS physically interacts with VASA, an RNA helicase thought to regulate mRNA metabolism. I identified two murine genes, SSB-1 and SSB-4, that are similar to and likely homologues of gus. SSB-1, SSB-4 and GUS each contain two conserved regions, termed the SPRY domain and the SOCS box, respectively. SSB-1 and SSB-4 share about 75% sequence identity and about 70% identity with GUS. Both SSB-1 and SSB-4 RNA and protein were found to be express in mouse ovarian granulosa cells of all stages of folliculogenesis. These cells support oocyte development and also produce steroids. Unexpectedly, SSB-1 and SSB-4 were only weakly or not detectable in oocytes, that contrasts with the expression of GUS in Drosophila oocytes. However, SSB-1 mRNA and protein were expressed in male germ cells; specifically in spermatocytes and spermatids. SSB-1 in spermatids was localized in a specialized structure known as the chromatoid body. Although the function of this structure is not quite clear, it has been compared to nuage, and one of its components is MVH, the murine homologue of VASA. Finally, using RNAi technology, SSB-1 was transiently depleted SSB-1 from a granulosa cell line. These cells showed a transient decrease in expression of the gene encoding P450scc, the rate-limiting enzyme in steroid synthesis. Preliminary results also indicated a decrease in progesterone synthesis. Taken together, these results establish the expression pattern of murine homologues of Drosophila GUS in mouse ovary and testis, reveal it might play function in translation regulation in male spermatogenesis, and identify a potential role in steroidogenesis by ovarian granulosa cells.

Thesis (Ph.D.)--University of Alabama at Birmingham, 2010. / Title from PDF title page (viewed on June 25, 2010). Includes bibliographical references.

No description available.

Thesis (Ph.D.)--University of Alabama at Birmingham, 2009. / Title from PDF title page (viewed on Feb. 2, 2010). Includes bibliographical references.

Angiotensin II (Ang II) promotes vascular disease and hypertension, in part, by activating the interleukin-6 (IL-6)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. Extensive studies have demonstrated that SOCS3 plays an important role in suppressing the IL-6/STAT3 pathway in the immune system and in cancer biology. In contrast, the functional importance of SOCS3 in cardiovascular disease is largely unknown. Thus, the overall goal of these studies was to investigate the role of SOCS3 in models of Ang II-dependent vascular disease and hypertension. To examine direct effects of Ang II on the vessel wall, carotid arteries from SOCS3 haplodeficient (SOCS3+/-) mice and wild-type littermates (SOCS3+/+) were incubated with the peptide or vehicle for 22 hrs, followed by examination of endothelial function using acetylcholine. Relaxation to acetylcholine was similar in all arteries incubated with vehicle. A low concentration of Ang II (1 nmol/L) did not affect acetylcholine-induced vasodilation in SOCS3+/+ mice, but reduced responses in arteries from SOCS3+/- mice by ~50% (P<0.05). This Ang II-induced endothelial dysfunction in SOCS3+/- mice was prevented by inhibitors of NF-êB or STAT3, an IL-6 neutralizing antibody, or a scavenger of superoxide. Responses to nitroprusside, an endothelium-independent vasodilator, were similar in all groups. To test the importance of SOCS3 in vivo, mice were infused systemically with a pressor dose of Ang II (1.4 mg/kg per day) or vehicle for 14 days via osmotic mini-pumps. Acetylcholine-induced vasodilation in carotid and resistance arteries in brain from SOCS3+/- mice was reduced by ~60% (P<0.05). Surprisingly, genetic deficiency in SOCS3 prevented the majority of Ang II-induced endothelial dysfunction without affecting the pressor response to Ang II. To investigate potential mechanisms underlying divergent results when studying effects of local versus systemic effects of Ang II, we performed bone marrow transplantation followed by infusion of vehicle or Ang II for two weeks. Lethally irradiated WT (CD45.1) mice reconstituted with SOCS3+/- bone marrow were protected from Ang II-induced endothelial dysfunction (P<0.05), while reconstitution of irradiated SOCS3+/- mice with WT (CD45.1) bone marrow exacerbated Ang II-induced vascular dysfunction (P<0.05). WT (CD45.1) into SOCS3+/+ and SOCS3+/- into SOCS3+/- bone marrow chimeras exhibited vascular function consistent with non-irradiated controls. In addition, the pressor response to Ang II was reduced by ~50% in WT mice reconstituted with bone marrow from SOCS3+/- mice (P<0.05). These data suggest that SOCS3 exerts divergent or context-dependent effects depending on whether vascular dysfunction was due to local versus systemic administration of Ang II. SOCS3 deficiency in the vessel wall enhanced local detrimental effects of Ang II on vascular function. In contrast, bone marrow-derived cells that are haplodeficient in SOCS3 protect against systemically administered Ang II and the resulting vascular dysfunction and hypertension. To my knowledge, these are the first experimental studies that begin to define the importance of SOCS3 in Ang II-induced hypertension and endothelial dysfunction. Results obtained from these experiments provide new insight into mechanisms which regulate oxidative stress and inflammation within the vasculature. The studies also revealed that bone marrow-derived cells that are haplodeficient in SOCS3 protect against pressor and endothelial effects of Ang II. These findings may eventually contribute to the development of novel therapeutic approaches for hypertension and hypertension associated end-organ damage.

Thesis (Ph. D.)--Cornell University, January, 2007. / Vita. Includes bibliographical references (leaves 92-106).

The duration and intensity of the JAK/stat signaling must be tightly regulated to prevent excessive transcriptional response and to reset the pathway to receive additional signals. Socs are the largest class of these regulators in mammals. Eight Socs genes have been found in mammals. CIS, and SOCS1-3, the canonical Socs, are transcriptionally activated by and down-regulate the JAK signaling. Socs4-7, the non-canonical Socs, are less studied and their relationship with the JAK/STAT pathway has not been well established. The Drosophila genome encodes three non-canonical Socs homologues, Socs16D, Socs36E, and Socs44A. Expression of Socs36E is controlled by the JAK pathway and misexpression causes phenotypes similar to that from reduction of JAK in both ovary and wing, which may make it functionally more similar to the canonical Socs. Expression of Socs44A is not controlled by the JAK pathway and misexpression causes JAK mutant phenotypes in wing but not in ovary. Imprecise excision mutants of the three Socs genes have been generated by us and have no visible phenotypes. The mutants of Socs36E and Socs44A significantly enhance the tumor formation in hopTum-l mutant, a gain-of-function mutation of the JAK/STAT pathway. The function of Drosophila Socs will be further studied with different strategies.

Orientador: Ana Paula de Souza Pardo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-22T12:44:41Z (GMT). No. of bitstreams: 1 Guedes_RogerAntoniaci_M.pdf: 960151 bytes, checksum: c0a68bdbdf663d427c182550b1d9fa14 (MD5) Previous issue date: 2013 / Resumo: A periodontite é caracterizada pela inflamação do periodonto, o tecido de suporte dos dentes. Este processo inflamatório pode evoluir da fase aguda para a fase crônica, acarretando severa destruição dos tecidos periodontais como também grave perda de inserção dos dentes ao osso alveolar. É evidente que o acúmulo de patógenos periodontais sobre a superfície dos dentes desencadeia a doença, porém seu agravamento e severidade também são dependentes de fatores ambientais, socioeconômicos, tabagismo, condição de saúde sistêmica e carga genética dos indivíduos. Desta forma, vários pesquisadores têm se dedicado a estudar a influência dos polimorfismos genéticos sobre a suscetibilidade e/ou risco aumentado à doença periodontal, uma vez que estes podem exercer efeito sobre o prognóstico da periodontite crônica. Estudos têm relatado associação entre vários polimorfismos genéticos com a inflamação periodontal. Há ainda estudos em larga escala onde grande parte do genoma (GWA) foi investigado, relatando efeito da genética do hospedeiro sobre a resposta à doença. Desde modo, considerando a hipótese de associação entre periodontite e polimorfismos no gene SOCS1 que expressa uma proteína chave no controle da via intracelular JAK/STAT ativada por diversas citocinas pró-inflamatórias presentes na inflamação periodontal, nosso objetivo neste estudo foi estudar a frequência dos genótipos, alelos e haplótipos dos polimorfismos SOCS1-1478 (rs33989964) e SOCS1-820 (rs33977706) em grupo de indivíduos com saúde periodontal e indivíduos com periodontite crônica, na tentativa de observar associação entre variações no gene SOCS1 com a doença periodontal crônica. Para tal, DNA genômico foi purificado de células epiteliais bucais obtidas por meio de enxágue com dextrose a 3%. Após, os genótipos foram identificados com a utilização das técnicas de PCR/ RFLP/ eletroforese. Análises estatísticas possibilitaram a observação da associação do polimorfismo SOCS1 -820 (rs33977706) com os casos de periodontite crônica mais severa / Abstract: The periodontitis is characterized by the periodontium inflammation, the supporting tissue of the teeth. This inflammatory disorder might evolve from the acute to the chronic phase, causing severe periodontal tissue destruction as well as teeth insertion loss in the alveolar bones. It is evident that the accumulation of periodontal pathogens on the teeth surface origins the disease, yet its aggravation and severity also depend on socioeconomic and environmental factors, smoking, systemic health condition and the genetic background of the subjects. Thus, several researchers have focused their studies on the influence of the genetic polymorphisms in the susceptibility and/or increased risk to the periodontal disease, once they might play a role on the chronic periodontitis prognosis. Studies have shown association between several genetic polymorphisms and periodontal inflammation. Still, there are large-scale studies in which the majority of the genome (GWA) has been investigated, reporting genetic host roles as responses to the disease. Thus, considering the hypothesis of association between periodontitis and polymorphisms in the SOCS1 gene which expresses a key protein in the control of the intracellular JAK/STAT via activated by varied pro-inflammatory cytokines found in the periodontal inflammation, we aimed to study the frequency of genotypes, alleles and haplotypes of the polymorphisms SOCS1-1478 (rs33989964) and SOCS1-820 (rs33977706) in a healthy periodontal subjects group and in a chronic periodontal subjects group, attempting to observe association between variations in the SOCS1 gene and the chronic periodontal disease. To do so, genomic DNA was purified from mouth epithelial cells collected through 3% dextrose rinse. Afterwards, the genotypes were identified by the use of PCR/RFLP electrophoresis techniques. Statistical analysis allowed us to observe association of SOCS1-820 polymorphism (rs33977706) with more severe chronic periodontitis cases / Mestrado / Histologia e Embriologia / Mestre em Biologia Buco-Dental

Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2014-09-18T13:07:03Z No. of bitstreams: 1 Gabriela da Silva Cruz. Avaliação... 2014.pdf: 1237079 bytes, checksum: 7beefa52e21bd18ac4325a1c493249ba (MD5) / Made available in DSpace on 2014-09-18T13:07:04Z (GMT). No. of bitstreams: 1 Gabriela da Silva Cruz. Avaliação... 2014.pdf: 1237079 bytes, checksum: 7beefa52e21bd18ac4325a1c493249ba (MD5) Previous issue date: 2014 / Fundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Salvador, BA, Brasil / O Trypanosoma cruzi é um parasita intracelular e agente causador da doença de Chagas, que afeta milhões de pessoas em todo o mundo. Sabe-se que durante os processos de inflamação, regeneração e fibrose desencadeados pelo T. cruzi no hospedeiro há a participação de diversos mediadores e fatores. O objetivo deste trabalho foi avaliar a associação entre polimorfismos de nucleotídeos únicos com as formas clínicas e o grau de fibrose em pacientes com doença de Chagas. Os polimorfismos foram analisados por PCR em tempo real. Foram incluídos no estudo 55 pacientes com diagnóstico de doença de Chagas e classificados de acordo com a forma clínica da doença, sendo que 17 apresentavam a forma indeterminada, 15 a forma cardíaca sem disfunção ventricular e 23 a forma cardíaca com disfunção ventricular. Os genótipos CA dos polimorfismos do gene LGALS3 (rs4644 e rs4652); AG e GG do SOCS3 (rs4969170); CT e TT do IL-28B (rs12979860 e 8099917, respectivamente); AG, AG, CC, AG e AG do CLDN-1 (rs10212165, rs3909582, rs9865082, rs9880018 e rs9848283, respectivamente); e CC do CCL5 (rs2280789) foram estatisticamente mais frequentes em pacientes com a forma cardíaca do que com a forma indeterminada da doença. Com relação ao grau de fibrose, os genótipos CC dos polimorfismos do gene LGALS3 (rs4644 e rs4652); AA do SOCS3 (rs4969170); CC do rs12979860 e TT do rs8099917 do IL-28B; AA do rs10212165, AA, AG e GG do rs3909582, CC e CT do rs9865082, AG e GG do rs9880018 e AA do rs9848283 do gene CLDN1; e CC do CCL5 (rs2280789) foram estatisticamente mais frequentes em indivíduos com fibrose cardíaca <15% quando comparados com o grupo com fibrose ≥15%. Diante do exposto concluimos que os polimorfismos analisados podem ser úteis como futuros biomarcadores para estadiamento e conduta terapêutica em pacientes com doença de Chagas. / Trypanosoma cruzi is an intracellular parasite and the agent that causes Chagas disease, which affects millions of people worldwide. Several factors and mediators are known to actively participate in the inflammation, fibrosis and tissue regeneration, which is triggered by T. cruzi within the host. The aim of this study was to evaluate the association of single nucleotide polymorphisms with clinical forms and rate of fibrosis in Chagas disease patients. The polymorphisms were analyzed by real-time PCR. The study consisted of 55 Chagas disease patients that were classified according to the clinical form of the disease, including 17 patients presenting the indeterminate form, 15 patients presenting the cardiac form without ventricular dysfunction and 23 patients presenting the cardiac form with ventricular dysfunction. The genotypes of CA of LGALS3 gene polymorphisms (rs4644 and rs4652); AG and GG of SOCS3 (rs4969170); CT and TT of IL-28B (rs12979860 and 8099917, respectively); AG, AG, CC, AG and AG of CLDN-1 (rs10212165, rs3909582, rs9865082, rs9880018 and rs9848283, respectively); and CC of CCL5 (rs2280789) were significantly more frequent in patients presenting the cardiac form compared to patients presenting the indeterminate form. Regarding the degree of fibrosis, the CC genotype of polymorphisms of the genes LGALS3 (rs4644 and rs4652); AA of SOCS3 (rs4969170); CC of rs12979860 and TT of rs8099917 of the IL-28B; AA of rs10212165 and AA, AG and GG of rs3909582, CC and CT of rs9865082, AG and GG of rs9880018 and AA of rs9848283 of the gene CLDN1; and CC of CCL5 (rs2280789) were statistically more frequent in patients presenting <15% cardiac fibrosis when compared to patients presenting fibrosis ≥15%. Taken together, our results suggest that the polymorphisms analyzed may be useful biomarkers for therapeutic management of patients with Chagas disease.

No description available.