Cohn N S, Mitchell J P, van den Broek K
Histochemistry. 1983;79(3):353-64. doi: 10.1007/BF00491771.
Squash preparations of Pisum sativum fourth internode tissue were stained with a combined Feulgen and dinitrofluorobenzene (DNFB) procedure. Nuclei from differentiating xylem vessel elements, phloem sieve tube elements and phloem fibres were measured for their DNA and protein contents with a Zeiss scanning cytophotometer linked to an interactive computer system. Nuclei were examined from both slowly growing and more rapidly growing internodes. A computer program was constructed to calculate nuclear protein alone as well as the ratio of DNFB (protein) to Feulgen (DNA) staining in each 0.5 X 0.5 micron measuring point. Nuclei were assigned to each of ten interphase fractions based on DNA content, nuclear area and percent condensed chromatin. There was a slight increase of nuclear protein during G1, a gradual increase in S, and a continued, often sharper, rise as G2 proceeded. In all three cell types, there was, on the average, a higher protein content throughout interphase in nuclei from the more rapidly growing internodes than from the slower growing ones. A population of fibre nuclei designated G0, however, differed from phloem and xylem G0 nuclei in the pattern of protein change. The nucleolar protein/DNA ratios of xylem nuclei increased in G1, showed no significant change in S, but increased thereafter.
用福尔根和二硝基氟苯（DNFB）联合染色法对豌豆第四节间组织的压片标本进行染色。使用与交互式计算机系统相连的蔡司扫描细胞光度计，测量正在分化的木质部导管分子、韧皮部筛管分子和韧皮部纤维细胞核中的DNA和蛋白质含量。对生长缓慢和生长较快的节间的细胞核都进行了检测。构建了一个计算机程序，用于计算每个0.5×0.5微米测量点的细胞核蛋白质含量以及DNFB（蛋白质）与福尔根（DNA）染色的比率。根据DNA含量、核面积和浓缩染色质百分比，将细胞核分为十个间期组分。在G1期细胞核蛋白质略有增加，在S期逐渐增加，并随着G2期的进行持续增加，且通常增加更为明显。在所有三种细胞类型中，平均而言，生长较快节间的细胞核在整个间期的蛋白质含量高于生长较慢节间的细胞核。然而，一群被指定为G0的纤维细胞核在蛋白质变化模式上与韧皮部和木质部的G0细胞核不同。木质部细胞核的核仁蛋白质/DNA比率在G1期增加，在S期无显著变化，但此后增加。
