DNA, RNA, PROTEIN AND HETEROCHROMATIN CHANGES DURING EMBRYO DEVELOPMENT AND GERMINATION OF SOYBEAN (GLYCINE-MAX L)
DNA, RNA, PROTEIN AND HETEROCHROMATIN CHANGES DURING EMBRYO DEVELOPMENT AND GERMINATION OF SOYBEAN (GLYCINE-MAX L)
复制标题
DOI：
10.1007/bf01006069
复制
发表时间：
1983-01-01
期刊：
影响因子：
--
通讯作者：
MIKSCHE, JP
中科院分区：
文献类型：
--
作者：
DHILLON, SS;MIKSCHE, JP
用细胞光度法测定了发育中的大豆种子的DNA、RNA、蛋白质和异染色质。大豆基因组2C DNA平均含量为2.64 pg，胚轴核DNA含量在胚发育过程中无显著变化；细胞停止分裂后，子叶细胞核DNA含量从3.58 pg增加到5.49 pg，内多倍体细胞核数量从26%增加到48%，DNA含量从4.45 pg增加到5.49 pg。在胚胎发育过程中，RNA和蛋白质含量的变化与DNA含量的变化大体相似。这可以解释为大豆子叶DNA水平的增加导致胚胎发生过程中蛋白质合成能力的增加。在萌发的前15天，子叶内多倍体核的数量从46%下降到4%，这种下降被解释为DNA的降解，为早期胚胎生长提供了核苷和磷酸盐的来源。随后的衰退（萌发后15至20天）与年龄有关，类似于叶片衰老，因为内多倍体核的百分比保持不变，而不活细胞的数量增加。与休眠子叶相比，衰老子叶的RNA和蛋白质分别丢失了73%和80%，而DNA仅丢失了20%。异染色质（浓缩染色质）测量表明，代谢不活跃的休眠和衰老子叶细胞核的异染色质含量比幼苗绿色子叶细胞核平均多33%。
DNA, RNA, protein and heterochromatin were measured cytophotometrically in developing soybean (G. max) seeds. The average 2C DNA content for the soybean genome was 2.64 pg. The amounts of nuclear DNA in embryo axes showed no significant change during embryo development; the DNA content in cotyledon nuclei increased significantly from 3.58 to 5.49 pg. The number of endopolyploid nuclei increased from 26 to 48% and the DNA content from 4.45 to 5.49 pg after cessation of cell division. The changes in RNA and protein content during embryo development were in general similar to those in DNA content. This can be interpreted that increased DNA levels in soybean cotyledons generated the protein synthesizing capacity during embryogeny increase. During the first 15 days of germination, the number of endopolyploid nuclei in cotyledons declined from 46 to 4%, and this decline is interpreted as DNA degradation, providing a ready source of nucleosides and phosphates during early embryo growth. A later decline (between 15 and 20 days after germination) was age-related, similar to leaf senescence, because the percentage of endopolyploid nuclei remained unchanged, while the number of nonviable cells increased. In senescing cotyledons, 73 and 80% of RNA and protein, but only 20% of DNA, were lost, as compared to dormant cotyledons. The heterochromatin (condensed chromatin) measurements indicated that nuclei of metabolically inactive dormant and senescent cotyledon nuclei contained an average of 33% more heterochromatin than nuclei from the green cotyledons of seedlings.