Kupriyanova N S, Nechvolodov K K, Korsunenko A V
Mol Gen Mikrobiol Virusol. 2014(3):12-7.
Tandem repetitions of rDNA provide so-called nuclear organizations (NOR). On the other hand, rDNA-structures are observed in some NOR chromosomes. It was demonstrated that, in addition to ribosome biogenesis, nucleoli provided a number of functions: cell cycle regulation, stress-induced response, transcription regulation, which often induced cell cascades. The mechanisms of the induction of rDNA segments in NOR chromosomes are obscure and require further research. About 1/3 repetitions are associated with nucleoli and SINE/Alu repetitions, homogeneous repetition, and tandem repetition. Perhaps, relative position of nucleoli and chromosomes may facilitate/prevent interaction of chromosomes with rDNA clusters. The variability of two larger repetitions in the central part of rMGS, LR1, and LR2 similar by -90% and separated by several hundred pairs of bases from each other was studied in our previous works. This work was devoted to the search for the LR1-LR2 segments in other chromosomes, characterization of their terminal tips at rupture points and genome areas of incorporation of the LR1-LR2 segments.