CHANGING RATES OF HISTONE MESSENGER-RNA SYNTHESIS AND TURNOVER IN DROSOPHILA EMBRYOS
CHANGING RATES OF HISTONE MESSENGER-RNA SYNTHESIS AND TURNOVER IN DROSOPHILA EMBRYOS
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DOI：
10.1016/0092-8674(80)90435-3
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发表时间：
1980-01-01
期刊：
影响因子：
64.5
通讯作者：
LENGYEL, JA
中科院分区：
文献类型：
--
作者：
ANDERSON, KV;LENGYEL, JA
通过体内和体外标记的胚胎RNA与重组质粒cDm500的黑腹果蝇组蛋白DNA的杂交来确定黑腹果蝇胚胎中组蛋白mRNA的合成和周转率。存在大量母体组蛋白 mRNA 储存，相当于至少 7 倍。每个胚胎 5 类组蛋白 mRNA 各有 107 个拷贝。组蛋白 mRNA 的胚胎合成在产卵后 90 分钟开始，使组蛋白基因成为第一个被胚胎细胞核转录的基因。胚胎组蛋白 mRNA 在胚盘和原肠胚阶段迅速积累。每个胚胎组蛋白 mRNA 合成率的峰值与每个胚胎 DNA 合成率的峰值一致，发生在产卵后 6 小时。 6小时后，随着每个胚胎DNA合成速率的降低，每个胚胎组蛋白mRNA合成速率和组蛋白mRNA总质量均急剧下降。每个基因的组蛋白 mRNA 合成率在产卵后第一个 13 小时内下降了 60 倍以上，从 2 小时时每个基因分钟 1.3-2.5 个拷贝下降到 13 小时时每个基因分钟 0.02-0.03 个拷贝。每个胚胎的组蛋白 mRNA 质量和早期胚胎发生的多个阶段新合成的组蛋白 mRNA 的积累速率的测量表明，组蛋白 mRNA 的细胞质半衰期缩短了大约 10%。黑腹果蝇早期发育过程中的 7 倍，从胚盘的 2.3 小时到原肠胚形成结束时的 20 分钟。黑腹果蝇发育中组蛋白基因的表达水平受母体 mRNA 库的大小、组蛋白 mRNA 合成速率的变化以及组蛋白 mRNA 周转速率的变化控制。
The rates of synthesis and turnover of histone mRNA in D. melanogaster embryos were determined by hybridization of in vivo and in vitro labeled embryonic RNA to D. melanogaster histone DNA of the recombinant plasmid cDm500. There is a large store of maternal histone mRNA, equivalent to at least 7 .times. 107 copies of each of the 5 classes of histone mRNA per embryo. Embryonic synthesis of histone mRNA begins at 90 min after oviposition, making the histone genes among the 1st to be transcribed by embryonic nuclei. Embryonic histone mRNA accumulates rapidly during the blastoderm and gastrula stages. The peak in the rate of histone mRNA synthesis per embryo coincides with the peak in the rate of DNA synthesis per embryo, which occurs at 6 h after oviposition. After 6 h, as the rate of DNA synthesis per embryo decreases, the rate of histone mRNA synthesis and the total mass of histone mRNA per embryo both drop sharply. The rate of histone mRNA synthesis per gene falls > 60-fold in the 1st 13 h after oviposition, from 1.3-2.5 copies per gene-min at 2 h to 0.02-0.03 copies per gene-min at 13 h. Measurements of the mass of histone mRNA per embryo and of the rate of accumulation of newly synthesized histone mRNA at a number of stages of early embryogenesis suggested that the cytoplasmic half-life of histone mRNA decreases .apprx. 7-fold during early D. melanogaster development, from 2.3 h at blastoderm to 20 min by the end of gastrulation. The level of expression of histone genes in D. melanogaster development is controlled by the size of the maternal mRNA pool, changes in the rate of histone mRNA synthesis, and changes in the rate of histone mRNA turnover.