Gene expression in mature neutrophils

描述（由申请人提供）：中性粒细胞提供宿主抵抗微生物感染的第一道防线，并在炎症和组织损伤中发挥重要作用。以往的研究表明，中性粒细胞中的RNA表达的转录反应非常活跃的激活各种刺激。我们在终末分化的骨髓细胞系模型中的研究也表明，大量转录因子的mRNA水平在细胞成熟过程中发生变化。现在，我们提出了一个协调和全面的调查转录区域和调节转录活性的发展和成熟的中性粒细胞。我们将调查： 1.“小说”成绩单我们将使用平铺阵列来确定细胞特异性和新的转录（即不对应于已知的基因）在静息和活化的外周血中性粒细胞和NB4早幼粒细胞白血病细胞在维甲酸诱导的终末分化表达的链。 2.转录因子。我们将使用染色质免疫沉淀和启动子和基因组阵列，以确定启动子结合的序列特异性转录因子在静息和活化的中性粒细胞表达。我们还将研究在NB4细胞分化过程中哪些基因启动子被转录因子结合，以确定新的因子是否影响重要的下游靶点。 3.染色质结构和重塑蛋白：我们将使用寡核苷酸平铺阵列来测试中性粒细胞是否通过改变DNA与染色质重塑蛋白或特异性修饰的组蛋白的结合来调节激活反应。我们还将确定特定的启动子序列与染色质修饰蛋白和修饰的组蛋白在NB4细胞的终末分化过程中的关联。 4. DNA甲基化：使用互补系统，以确定甲基化状态和胞嘧啶残基的位置，内和外的CpG岛，我们将研究在激活的中性粒细胞和NB4细胞的髓系成熟过程中的胞嘧啶甲基化位点的变化。鉴定新的嗜中性粒细胞特异性基因和调控网络可以为增强宿主防御、减轻炎症和治疗骨髓生成障碍提供新的靶点。

DESCRIPTION (provided by applicant): Neutrophils provide the first line of host defense against microbial infections and play a major role in inflammation and tissue damage. Previous studies of RNA expression in neutrophils have revealed a remarkably vigorous transcriptional response to activation by various stimuli. Our studies in a myeloid cell line model of terminal differentiation have also indicated that mRNA levels for a large number of transcription factors change during cell maturation. We now propose a coordinated and comprehensive investigation of the transcribed regions and the regulators of transcriptional activity in developing and mature neutrophils. We will investigate: 1. "Novel" transcripts. We will use tiling arrays to determine the cell specificity and strandedness of novel transcripts (i.e. not corresponding to known genes) expressed in resting and activated peripheral blood neutrophils and in NB4 promyelocytic leukemia cells during retinoid-induced terminal differentiation. 2. Transcription factors. We will use chromatin immunoprecipitation and both promoter and genomic arrays to identify promoters bound by sequence-specific transcription factors expressed in resting and activated neutrophils. We will also investigate which gene promoters are bound by transcription factors during NB4 cell differentiation to determine whether the novel factors affect important downstream targets. 3. Chromatin structure and remodeling proteins: We will use oligonucleotide tiling arrays to test whether neutrophils regulate activation responses by alterations in the association of DNA with chromatin remodeling proteins or specifically modified histones. We will also determine the association of specific promoter sequences with chromatin modifying proteins and modified histones during terminal differentiation of NB4 cells. 4. DNA methylation: Using complementary systems to determine the methylation status and location of cytosine residues, both within and outside CpG islands, we will investigate changes in the sites of cytosine methylation in activated neutrophils and during myeloid maturation in NB4 cells. Identification of novel neutrophil-specific genes and regulatory networks could provide new targets for augmentation of host defense, attenuation of inflammation, and treatments of disorders of myelopoiesis.