Autoradiographic study of protein and RNA formation during early development of Drosophila eggs.
Autoradiographic study of protein and RNA formation during early development of Drosophila eggs.
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DOI：
10.1016/0012-1606(76)90185-8
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发表时间：
1976-04
影响因子：
2.7
通讯作者：
M. Zalokar
中科院分区：
文献类型：
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作者：
M. Zalokar
将黑腹果蝇卵在氚尿苷、缬氨酸和苯丙氨酸中孵化。用闪烁计数法检测其对TCA不溶性物质的摄取和掺入。胚胎期之前，尿苷的掺入很少。在胚胎期，卵子摄取2.4Pmoles/hr的尿苷，并在RNA中掺入0.13Pmoles(假设前体的比活性没有稀释)。氨基酸的摄取随着胚胎年龄的不同而不同；未受精的鸡蛋合成的蛋白质与受精卵一样多。在尿苷中孵育的卵子的放射自显影显示，在胚泡形成开始之前，细胞核中缺乏RNA合成。在此阶段之前的少量尿苷掺入是由于线粒体。直到胚层，氨基酸的掺入在细胞质中是均匀的，没有卵黄颗粒的掺入。在原肠发育过程中出现了标记的区域差异。极细胞在胚胎期不形成RNA，原肠形成期开始形成。相反，极细胞的蛋白质标记在胚泡和早期原肠胚中很强。这些结果表明，合子基因组在胚胎期之前表达的可能性不大。
Permeabilized eggs ofDrosophila melanogasterwere incubated in tritiated uridine, valine, and phenylalanine. The uptake and incorporation into TCA-insoluble material were measured by scintillation counting. There was very little incorporation of uridine before the blastoderm stage. At the blastoderm stage, the egg took up 2.4 pmoles/hr of uridine and incorporated 0.13 pmoles into RNA (assuming no dilution of specific activity of the precursor). The uptake of amino acids varied with the age of the embryo; virgin eggs synthesized about as much protein as fertilized eggs. Autoradiography of eggs incubated in uridine showed a lack of RNA synthesis in nuclei until the start of the blastoderm formation. The small amount of uridine incorporation before this stage was due to mitochondria. Incorporation of amino acids was uniform in the cytoplasm until the blastoderm; there was no incorporation by yolk granules. Regional difference in labeling appeared during gastrulation. The pole cells did not form RNA during the blastoderm stage, formation started during gastrulation. Protein labeling of the pole cells, on the contrary, was very strong in the blastoderm and early gastrula. These results indicate that the expression of zygotic genome before the blastoderm stage is unlikely.