Volume 5 Issue 2, December 1995: 155-164
ORIGINAL ARTICLES
Studies on the mitotic chromosome scaffold of Allium sativum
Studies on the mitotic chromosome scaffold of Allium sativum
Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024, China.
Correspondence: SHUI HAO
An argentophilic structure is present in the metaphase chromosomes of garlic (Allium sativum). Cytochemical studies indicate that the main component of the structure is non-histone proteins (NHPs). The results of light and electron microscopic observations reveal that the chromosme NHP scaffold is a network whi ch is composed of fibres and granules and distributed throughout the chromosomes. In the NHP network, there are many condensed regions that are connected by relatively looser regions. The distribution of the condensed regions varies in individual chromosomes. In some of the chromosomes the condensed regions are longitudinally situated in the central part of a chromatid while in others these regions appear as coil-like transverse bands. At early metaphase, however, the connective scaffold materials between the two sister chromatids disappear gradually and the chromatids begin to separate from one another at their ends, but the chromatids are linked together in the centromeric region until anaphase. This connection seems to be related to the special structure of the NHP scaffold formed in the centromeric region. The morphological features and dynamic changes of the chromosome scaffold are discussed.
FULL TEXT | PDF
Browse 1677
