Author/Editor		Comino, A
Title		Structure and function of CDC6 gene in the cell cycle of yeast Saccharomyces cerevisiae
Type		monografija
Place		Ljubljana
Publisher		Medicinska fakulteta
Publication year		1995
Volume		str. 144
Language		eng
Abstract		The function of an essential gene CDC6 in the cell division cycle of Saccharomyces cerevisiae in correlation with its predicted structure has been studied in this work. To understand the role of CDC6 gene in the yeast cell cycle, the execution time of the gene product has been determined by using double shift experiments with microtubule inhibitor nocodazole. This drug allows spindle pole bodies duplication but inhibits their separation. It also prevents spindle formation; already formed spindles collapse in the presence of nocodazole. Interdependency of the gene product with mitotic spindle function was unravelled by this system. This correlation represents a new data about the function of CDC6 and substantially changes the view on its role in the yeast cell cycle. To understand the cause of mortality of nocodazole synchronised cells after applying non-permisive temperature, Lsd-12 diploid strain homozygous for CDC6 was used. By following genetic events on chromosome VII it was found that 80 to 90 pct. of genetic events leading to cycloheximide resistance were due to the various types of recombination and gene conversion. The rest was mainly due to the chromosome-loss. It was also unravelled that synchronisation of cells increase the frequency of recombination compared to the asynchronous strain. In addition, we have followed by Fluorescence Activated Cell Sorter Analysis the DNA content in the population of CDC6 cells released from nocodazole synchronization to permisive and restrictive temperature in order to explain the mortality of cells at nonpermissive temperature. Aberrations in the cell cycle timimg of cdc6 mutant cells at non-permissive temperature were observed. These results demonstrate that CDC6 has an important role in the cell cycle control provided by a new, yet unknown mechanism. Studying the alpha-factor synchronised population of mutant cells, interaction of the CDC6 gene product with chromosome segregation process was demonstrated.(trunc.)
Descriptors		SACCHAROMYCES CEREVISIAE GENES, CDC NOCODAZOLE CELL DIVISION CELL CYCLE