Maize nuclei

The cloning of the TT2 gene by T-DNA tagging was reported by Nesi et al. (2001). This gene encodes an R2R3 myb protein that shows similarity to the maize C1 protein. In order to test whether the TT2 protein functions as a transcriptional activator, Nesi et al. (2001) were able to show that this protein is localized in the nucleus, that the spatio-temporal expression... 

A word of caution should be noted at this juncture. The titration curve for the fluorochrome should be determined on the species of interest. Two species that vary widely with respect to nuclear DNA content may not have the same titration curves. For example, the titration curve of sorghum at 1.63 pg of DNA per 2C nucleus is much different than the titration curve of maize at 6.0 pg per 2C nucleus. After the proper staining conditions have been determined, the nuclei are ready for analysis. 

According to Ladonin and Spesivtsev (1974), maize tolerant to chloro-5-triazines stores the triazine taken up in the cytoplasm and in the sensitive pea it is stored in the nucleus, chloroplasts and mitochondria. They assume that the triazines are thus incorporated into proteins and nucleic acids as antimetabolites during the biosynthesis of internuclear nucleic acids. This may also be one of the explanations of the different sensitivity of plants to triazines. Black currant is also tolerant to 4 ppm simazine. According to Shone and Wood (1972) triazine translocated into the leaves of black currant cannot get from the tissue system into the mesophyll. The simazine taken up remains in the leaf veins and does not enter the chloroplasts. 

The biosynthesis of indolic compounds begins with the conversion of chorismate into anthranilate. Anthranilate is converted, through a series of five reactions, into the amino acid tryptophan, a precursor of which is indole itself. The genes that encode enzymes for the reactions from anthranilate to tryptophan are localized in the nucleus [18], however, the reactions probably occur in the chloroplast [19-21]. In Arabidopsis [18] and maize... 

Sharma PK, Baruah P (1975) Effect of auxins on yeast. Nucleus 18 124-128 Shen-Miller J, McNitt RE, Wojciechowski M (1978) Regions of differential cell elongation and mitosis, and root meristem morphology in different tissues of geotropically stimulated maize root apices. Plant Physiol 61 7-12... 

Behind the promeristem of the root tip is the region where cell enlargement and differentiation are the dominant processes. For instance, in the seedling maize root very few cell divisions are observed beyond 1 -5 mm from the root cap and it is in the 2nd and 3rd mm from the root cap that the most active linear extension by cell expansion takes place. By 5 mm from the root cap most of the roots cells are fully expanded and already their differentiation into the root tissues is well advanced. As earlier described the meristematic cells are isodiametric, small, have a high nucleus to cell volume ratio and are filled with c3rtoplasm. During cell expansion, not only is the cell... 

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