Dynamic organisation of prolactin gene expression in living pituitary tissue
Dynamic organisation of prolactin gene expression in living pituitary tissue
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DOI：
10.1242/jcs.060434
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发表时间：
2010-02-01
影响因子：
4
通讯作者：
White, Michael R. H.
中科院分区：
文献类型：
--
作者：
Harper, Claire V.;Featherstone, Karen;White, Michael R. H.
活细胞中的基因表达是高度动态的，但完整组织中基因表达的时间模式在很大程度上是未知的。哺乳动物脑垂体由几种混合的细胞类型组成，组织为相互作用的功能网络，以产生协调的激素分泌。活细胞成像被用来量化模式的报告基因表达在分散的催乳细胞或完整的垂体组织从细菌人工染色体（BAC）转基因大鼠，其中一个大的催乳素基因组片段指导荧光素酶或不稳定的增强型绿色荧光蛋白（d2 EGFP）的表达。催乳素启动子活性在转基因垂体不同区域随时间变化。虽然转录反应的幅度不同，所有区域的腺体显示类似的报告基因表达的总体模式超过50小时的时间内，这意味着整体协调的细胞行为。相比之下，酶分散的垂体细胞培养物显示不同细胞之间的启动子活性的不同步波动，这表明转录模式受到组织结构的限制。短期，高分辨率，单细胞分析催乳素-d2 EGFP转基因垂体切片制剂显示不同的转录模式与相邻细胞之间的相关性很小。总之，这些数据表明，垂体组织包括一系列的细胞系综，单独显示各种模式的短期随机行为，但在一起产生长期和长期的协调行为。
Gene expression in living cells is highly dynamic, but temporal patterns of gene expression in intact tissues are largely unknown. The mammalian pituitary gland comprises several intermingled cell types, organised as interdigitated networks that interact functionally to generate co-ordinated hormone secretion. Live-cell imaging was used to quantify patterns of reporter gene expression in dispersed lactotrophic cells or intact pituitary tissue from bacterial artificial chromosome (BAC) transgenic rats in which a large prolactin genomic fragment directed expression of luciferase or destabilised enhanced green fluorescent protein (d2EGFP). Prolactin promoter activity in transgenic pituitaries varied with time across different regions of the gland. Although amplitude of transcriptional responses differed, all regions of the gland displayed similar overall patterns of reporter gene expression over a 50-hour period, implying overall coordination of cellular behaviour. By contrast, enzymatically dispersed pituitary cell cultures showed unsynchronised fluctuations of promoter activity amongst different cells, suggesting that transcriptional patterns were constrained by tissue architecture. Short-term, high resolution, single cell analyses in prolactin-d2EGFP transgenic pituitary slice preparations showed varying transcriptional patterns with little correlation between adjacent cells. Together, these data suggest that pituitary tissue comprises a series of cell ensembles, which individually display a variety of patterns of short-term stochastic behaviour, but together yield long-range and long-term coordinated behaviour.