A Histochemical Study of Plant Nuclei in Rest and Mitosis

Abstract

Histochemical tests were made wich the resting as well as dividing nuclei in plants with FEULGEN's nucleai-reaction method for the test of thymusnucleic acid, MILLON'S, the xanthoproteic and the biuret reaction method for Proteins, and CHRISTELLER'S, CIACCIO's and other methods of testing for lipoids. The solution analysis method and staining according to PAPPENHEIM-UNNA'S method were also used as supplemen-tary means of testing the results obtained with the methods named above. The results we obtained with these methods are as follows:
1) The nuclear reticulum and chromosomes show reactions of thymusnucleic acid, lipoids and proteins.
2) In the chromosomes the thymusnucleic acid reaction is found exclusively in the spiral portion.
3) The chromosomes are far more easily dissolved by lipoid solvents and nucleoprotein solvents than the resting nucleus is (Tables 1 and 2).
4) Of the two morphological components f of chromosomes, the spiral portion and matrix, the former is more resistant to the action of lipoid solvents than the latter.
5) There is some evidente which suggests that certain material changes may take place in the nuclear components during mitosis.
6) The nucleus of Spirogyra sp. shows no thymusnucleic acid reaction but a protein reaction, forming a striking contrast to the other plants investigated.
7) The karyolymph show no positive result in any of the tests for thymusnucleic acid, Lipoids, and proteins, but the result obtained with the precipitation method suggests that there may be lipoid in the karyolymph.
8) The nucleolus is shown to contain lipoids, but no thymusnucleic acid.
9) The spindle fibers and the phragmoplast are shown to consist mainly of proteins and Lipoids in a mixed or a combined form.
In concluding, the authors wish to express their sintere thanks to Prof. Y. KUWADA for his kind guidance throughout the investigation.