IMPLICATIONS FOR BCD MESSENGER-RNA LOCALIZATION FROM SPATIAL-DISTRIBUTION OF EXU PROTEIN IN DROSOPHILA OOGENESIS
IMPLICATIONS FOR BCD MESSENGER-RNA LOCALIZATION FROM SPATIAL-DISTRIBUTION OF EXU PROTEIN IN DROSOPHILA OOGENESIS
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DOI：
10.1038/369400a0
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发表时间：
1994-06-02
期刊：
影响因子：
64.8
通讯作者：
HAZELRIGG, T
中科院分区：
文献类型：
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作者：
WANG, SX;HAZELRIGG, T
亚细胞RNA在不同细胞类型中的定位导致这些细胞中蛋白质的不对称分布（1,2）。bicoid （bcd）信使RNA定位于发育中的果蝇卵母细胞的前极，导致胚胎发生时bcd蛋白的浓度梯度急剧升高（3-6），bcd蛋白是一种激活前极发育所需的合子基因表达的转录因子（7-9）。exuperantia （exu）基因对于bcd mRNA的定位是必需的（3,4）。我们在雌性生殖细胞中表达了一种编码维多利亚绿荧光蛋白（GPP）（10）和exu蛋白（exu）融合的嵌合基因，并发现融合蛋白在果蝇的活细胞和固定细胞中都能发出强烈的荧光。该融合蛋白挽救了一个exu缺失等位基因，恢复了雌性的完全生育能力，并以与原生exu相似的时间和空间模式表达和定位。GFP标签的高灵敏度为Exu的亚细胞定位提供了重要的新细节。融合蛋白集中在环管中，在环管中，乳母细胞和卵母细胞之间进行运输。影响微管稳定性的药物如秋水仙碱和紫杉醇会改变颗粒的定位。我们认为这些颗粒是核糖核蛋白复合物或囊泡，它们沿着微管运输bcd mRNA并将其靶向到卵母细胞前皮层。
SUBCELLULAR RNA localization in different cell types leads to asymmetric distribution of proteins in these cells(1,2). The localization of bicoid (bcd) messenger RNA to the anterior pole of the developing Drosophila oocyte gives rise in embryogenesis to a steep concentration gradient of the bcd protein(3-6), a transcription factor that activates expression of zygotic genes needed for anterior development(7-9). The exuperantia (exu) gene is necessary for this localization of bcd mRNA(3,4). Here we express a chimaeric gene encoding a fusion between the Acquorea victoria green fluorescent protein (GPP)(10) and the exu protein (Exu) in female germ cells, and find that the fusion protein fluoresces strongly in both live and fixed cells during Drosophila oogenesis. The fusion protein rescues an exu null allele, restoring full fertility to females, and is expressed and localized in a temporal and spatial pattern similar to native Exu. The high sensitivity of the GFP tag provides important ne,v details on the subcellular localization of Exu. The fusion protein is found in particles concentrated at ring canals, where transport occurs between nurse cells and the oocyte. Drugs such as colchicine and taxol that affect microtubule stability alter localization of the particles. We propose that the particles are ribonucleoprotein complexes or vesicles which transport bcd mRNA along microtubules and target it to the anterior oocyte cortex.