Polysome structure in sea urchin eggs and embryos: an electron microscopic analysis.
Polysome structure in sea urchin eggs and embryos: an electron microscopic analysis.
复制标题
海胆卵和胚胎中的多核糖体结构:电子显微镜分析。
DOI:
10.1016/0012-1606(83)90364-0
复制
发表时间:
1983
影响因子:
2.7
通讯作者:
MillerJr,OL
中科院分区:
文献类型:
--
作者:
Martin,KA;MillerJr,OL
Modified chromatin-spreading techniques have been used to prepare reproducible spreads of polysomes for EM visualization. We have analyzed polysomes of sea urchin (Lytechinus pictus) eggs and embryos to elucidate some of the events which occur during the burst of protein synthetic activity following fertilization. We have confirmed that the rise in protein synthesis after fertilization is concomitant with the recruitment of messenger RNA molecules into polysomes. The presence of ribosome-free tails is a structural feature of polysomes in which the mRNA is being translated for the first time. This structural marker has allowed us to derive an elongation rate of 1.5–1.8 amino acids/sec and a transit time of 5 min for the average-sized polysome inL. pictusembryos at 16°C. We have also observed a difference between the structure and the average size of polysomes in the egg and embryo. Egg polysomes are longer (average size = 11.96 ribosomes,n= 671) than 1-hr embryo polysomes (average size = 7.14 ribosomes,n= 863) and 10% of the egg polysomes contain visible gaps while less than 1% of the 1-hr embryo polysomes contain internal ribosome-free regions. We speculate that such differences reflect the lower translation efficiency of the relatively dormant egg cell.
登录
查看更多内容
影响因子:
2.7
作者:
B. Brandhorst
通讯作者:
B. Brandhorst
影响因子:
2.7
作者:
T. Humphreys
通讯作者:
T. Humphreys
DOI:
10.1073/pnas.57.4.899
发表时间:
1967-01-01
影响因子:
11.1
作者:
EPEL, D
通讯作者:
EPEL, D
影响因子:
64.5
作者:
F. Wilt
通讯作者:
F. Wilt
影响因子:
64.8
作者:
M. B. Hille;Alegria Albers
通讯作者:
Alegria Albers