A 61-kb ring chromosome shows an ARS-dependent increase in its mitotic stability in the mcm2 mutant of yeast.
We have studied the effects of ARS addition and deletion on the maintenance of a 61-kb ring derivative of chromosome III in a minichromosome maintenance mutant of yeast carrying the mcm2-1 mutation. When this ring chromosome, CIIIR, had either of its two strong origins deleted, the resultant chromosome showed a much greater instability in the mutant as compared to that of the wild-type strain. Integration of more ARSs improved the maintenance of CIIIR in the mutant but not in the wild-type strain. Increase in the size of CIIIR, without any ARS addition, did not improve the stability in either strain. A spontaneous revertant for improved growth at 35 degrees C also co-reverted for minichromosome and CIIIR maintenance. The results suggest that ARS malfunctioning leads to minichromosome and chromosome loss from mutant cells, affecting their growth at higher temperatures.
Ray
A
A
Department of Biochemistry, Bose Institute, Calcutta, India.
Roy
N
N
Maitra
M
M
Sinha
P
P
D000251:Adenosine Triphosphatases / Q000096:biosynthesis / Q000235:genetics*; D053502:Arsenate Reductases; D053501:Arsenite Transporting ATPases; D002868:Chromosomal Proteins, Non-Histone; D015825:Chromosomes, Fungal; D004261:DNA Replication; D005656:Fungal Proteins / Q000235:genetics*; D017353:Gene Deletion; D005800:Genes, Fungal; D005838:Genotype; D016623:Ion Pumps; D008938:Mitosis; D009097:Multienzyme Complexes; D016254:Mutagenesis, Insertional; D010957:Plasmids; D015183:Restriction Mapping; D012303:Ring Chromosomes; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development; D029701:Saccharomyces cerevisiae Proteins
D002868:Chromosomal Proteins, Non-Histone; D005656:Fungal Proteins; D016623:Ion Pumps; D009097:Multienzyme Complexes; D029701:Saccharomyces cerevisiae Proteins; C506971:ARR2 protein, S cerevisiae; D053502:Arsenate Reductases; D000251:Adenosine Triphosphatases; D053501:Arsenite Transporting ATPases; C069199:MCM2 protein, S cerevisiae