The accumulation and translation of a spicule matrix protein mRNA during sea urchin embryo development.
The accumulation and translation of a spicule matrix protein mRNA during sea urchin embryo development.
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海胆胚胎发育过程中针状基质蛋白 mRNA 的积累和翻译。
DOI：
10.1016/0012-1606(89)90306-0
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发表时间：
1989
影响因子：
2.7
通讯作者：
Wilt,FH
中科院分区：
文献类型：
--
作者：
Killian,CE;Wilt,FH
在这份报告中，我们进一步表征的基因，编码的50 kDa的骨针基质蛋白（SM 50）的表达过程中的海胆Strongylocentrotus purpuratus。使用单链探针过量滴定技术定量测量SM 50 mRNA水平表明，SM 50转录物水平在原肠胚阶段达到每个胚胎8000至10，000个转录物的最大水平，代表每个原代间充质细胞120至200个SM 50 mRNA。分析在不同发育阶段分离的细胞核中的连续转录的实验表明，在初级间充质侵入时发生的SM 50 mRNA水平的急剧增加伴随着SM 50基因转录的增加。我们还分析了在不同发育阶段的多聚核糖体上存在的RNA序列。这些研究表明，SM 50 mRNA在开始积累时就存在于多聚核糖体上（这远远早于明显的骨针形成），并且SM 50 mRNA在随后的发育中保留在多聚核糖体上。根据这些数据对SM 50蛋白合成速率的估计，我们计算出在发育过程中通过4天的pluteus阶段积累的SM 50的最大量约为7.4 pg/胚胎。这种近似值与海胆胚胎中实际发现的SM 50含量一致。
In this report we further characterize the expression of the gene that encodes the 50-kDa spicule matrix protein (SM50) during development of the sea urchinStrongylocentrotus purpuratus. Quantitative measurements of SM50 mRNA levels using the single-stranded probe excess titration technique indicate that SM50 transcript levels attain a maximum level of 8000 to 10,000 transcripts per embryo by the gastrula stage, representing 120 to 200 SM50 mRNAs per primary mesenchyme cell. Experiments analyzing run-on transcription in nuclei isolated at different stages of development indicate that the sharp increase in SM50 mRNA levels occurring at the time of primary mesenchyme ingression is concomitant with an increase in transcription of the SM50 gene. We have also analyzed the RNA sequences present on polyribosomes at different stages of development. These studies indicate that SM50 mRNA is present on polyribosomes as soon as it begins to accumulate (which is well in advance of overt spicule formation) and SM50 mRNA remains on polyribosomes through subsequent development. From estimates of the rate of SM50 protein synthesis based on these data, we calculated that the maximum amount of SM50 accumulated during development through the 4-day pluteus stage is approximately 7.4 pg/embryo. This approximation is concordant with the amount of SM50 actually found in the sea urchin embryo.