Analysis of novel Steroidogenic Factor-1 targets in the human adrenal gland

Steroidogenic Factor-1 (SF-1, NR5A1) is a nuclear receptor transcription factor that plays a central role in adrenal and reproductive biology. In humans, SF-1 regulates adrenal development and disruption of SF-1 or its known targets is associated with impaired adrenal function. Therefore, the identification of novel SF-1 targets could reveal important new mechanisms in adrenal development and disease. This thesis describes three approaches to identifying SF-1 targets in NCI-H295R human adrenocortical cells. SF-1-dependent regulation of CITED2 and PBX1 was investigated since these factors regulate adrenal development in mice through pathways shared with Sf-1. Expression of CITED2 and PBX1 was confirmed in the developing human adrenal, and SF-1 was found to bind to and activate the CITED2 promoter and to cooperate with DAX1 to activate the PBX1 promoter. SF-1 binding was investigated using chromatin immunoprecipitation microarrays (ChIP-on-chip). These studies revealed that SF-1 binds to the extended promoter of 445 genes, including factors involved in angiogenesis. Angiopoietin 2 (ANGPT2) emerged as a key novel SF-1 target, confirmed by transactivational studies, suggesting that regulation of angiogenesis might be an important additional action of SF-1 during adrenal development and tumorigenesis. Global gene expression analysis following SF-1 overexpression revealed differential expression of 1058 genes, many of which are involved in steroidogenesis, lipid metabolism and cell proliferation. Bidirectional manipulation of SF-1 revealed a subset of positively regulated genes, including the known targets STAR and CYP11A1 and novel target SOAT1, a regulator of cholesterol esterification. Considering that defects in several SF-1 targets have been associated with adrenal disorders, mutational analysis of SOAT1 was performed in forty-three subjects with unexplained adrenal insufficiency but failed to reveal potentially disease-causing variants. Taken together, manipulation of SF-1 in human adrenal cells has expanded our knowledge of the many potential actions of SF-1 in the human adrenal gland

Sequential injection analysis: a powerful tool for routine soil and plant laboratories.

Sequential injection (SIA) present attractive characteristics for analyses in large scale. In SIA the analytical determination can be perfomed automatically reducing the number of steps usually involved in a chemical analysis. In order to laboratory dedicated to routine analyze, the determination of volatile nitrogen in silge and soil samples has been performed. The nitrogen content was deermined afther NH, on-line separation in alkaline conditions by using a gaseus diffision or a pervaporatioin unit for liquid separatioin. An ammonium tubular selective alectrode detector was used for determinations

ChIP-on-chip analysis reveals angiopoietin 2 (Ang2, ANGPT2) as a novel target of steroidogenic factor-1 (SF-1, NR5A1) in the human adrenal gland

The nuclear receptor steroidogenic factor-1 (SF-1, NR5A1) is a key regulator of adrenal and gonadal biology. Disruption of SF-1 can lead to disorders of adrenal development, while increased SF-1 dosage has been associated with adrenocortical tumorigenesis. We aimed to identify a novel subset of SF-1 target genes in the adrenal by using chromatin immunoprecipitation (ChIP) microarrays (ChIP-on-chip) combined with systems analysis. SF-1 ChIP-on-chip was performed in NCI-H295R human adrenocortical cells using promoter tiling arrays, leading to the identification of 445 gene loci where SF-1-binding regions were located from 10 kb upstream to 3 kb downstream of a transcriptional start. Network analysis of genes identified as putative SF-1 targets revealed enrichment for angiogenic process networks. A 1.1-kb SF-1-binding region was identified in the angiopoietin 2 (Ang2, ANGPT2) promoter in a highly repetitive region, and SF-1-dependent activation was confirmed in luciferase assays. Angiogenesis is paramount in adrenal development and tumorigenesis, but until now a direct link between SF-1 and vascular remodeling has not been established. We have identified Ang2 as a potentially important novel target of SF-1 in the adrenal gland, indicating that regulation of angiogenesis might be an important additional mechanism by which SF-1 exerts its actions in the adrenal gland

Estimativas de parâmetros genéticos e fenotípicos para pesos na raça Nelore Mocha em três regiões brasileiras.

O objetivo deste trabalho foi estimar herdabilidade e correlacoes de pesoso de zebuinos Nelore Mocho. O dados foram analisados pelo metodo dos quadrados minimos, cujos metodos estatisticos incluiram os efeitos ficos de ano e estacao de nascimento, sexo, regiao, interacao estavo e regiao e a covariavel idade da vaca ao parto, o efeito aleatorio de touro.Resumos expandidos

Sterol O-Acyltransferase 1 (SOAT1, ACAT) Is a Novel Target of Steroidogenic Factor-1 (SF-1, NR5A1, Ad4BP) in the Human Adrenal

Context: Steroidogenic factor-1 (SF-1, NR5A1, Ad4BP) is a master regulator of adrenal development and steroidogenesis. Defects in several known targets of SF-1 can cause adrenal disorders in humans.Objective: We aimed to identify novel targets of SF-1 in the human adrenal. These factors could be important regulators of adrenal development and steroidogenesis and potential candidates for adrenal dysfunction.Design: A gene discovery strategy was developed based on bidirectional manipulation of SF-1. Overexpression or knockdown of SF-1 in NCI-H295R human adrenocortical cells was used to identify a subset of positively-regulated SF-1 targets.Results: This approach identified well-established SF-1 target genes (STAR, CYP11A) and several novel genes (VSNL1, ZIM2, PEG3, SOAT1, and MTSS1). Given its role in cholesterol metabolism, sterol O-acyltransferase 1 (SOAT1, previously referred to as acyl-Coenzyme A: cholesterol acyltransferase 1, ACAT) was studied further and found to be expressed in the developing human fetal adrenal cortex. We hypothesized that impaired SOAT1 activity could result in adrenal insufficiency through reduced cholesteryl ester reserves or through toxic destruction of the adrenal cells during development. Therefore, mutational analysis of SOAT1 in a cohort of 43 patients with unexplained adrenal insufficiency was performed but failed to reveal significant coding sequence changes.Conclusions: Our reverse discovery approach led to the identification of novel SF-1 targets and defined SOAT1 as an important factor in human adrenal steroidogenesis. SF-1-dependent upregulation of SOAT1 may be important for maintaining readily-releasable cholesterol reserves needed for active steroidogenesis and during episodes of recurrent stress. (J Clin Endocrinol Metab 96: E663-E668, 2011

Repetibilidade dos pesos e ganho de peso do nascimento a desmama de bezerros da raça Nelore.

Repetibilidade do ganho de peso ao nascimento e a desmama

Desenvolvimento de linhagens e cultivares de tomateiro para o Nordeste do Brasil com resistencia a Tospovirose e Geminiviroses.

A região Nordeste produz anualmente cerca de 240 mil toneladas de tomate para processamento industrial, sendo esta atividade responsável pela absorção de grande contingente de mão-de-obra envolvido direta e indiretamente no cultivo e no processamento de tomate. As tospoviroses, transmitidas por tripes, e as geminiviroses, transmitidas por mosca-branca, vêm causando grandes reduções na produtividade do tomateiro no Nordeste do Brasil. O controle químico dos insetos vetores muitas vezes não diminui a incidência destas viroses no tomateiro, sendo comum a ocorrência de campos com 100% de plantas mostrando sintomas destas doenças. O uso da resistência genética, como um dos componentes do manejo integrado de pragas (MIP), parece ser a medida mais eficaz para o controle destas duas viroses