Possible Functional Structures in the Chromomere
The basis of each chromosome is a DNA molecule lying between its telomeres (Gruzdev and Reznik, 1981). The chromosome after partial deproteinization exhibits a set of long (60 – 90 kbp) DNA loops (Paulson and Laemmli, 1977) which in milder conditions are organized into rosette structures composed of short (about 5 kbp) loops (Okada and Comings, 1979). As the long loops are considered to represent the DNA molecules of the chromomeres (Okada and Comings, 1979) the short ones may correspond to the nucleomeres. Noted variations in the length of the loops and in the number of the rosette loops (Okada and Comings, 1979) may reflect variations in the genetical content of the chromomere. This means that there should exist a correspondence between the genetical units (genes, exons, introns) and the structural units of the chromomere.
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