[Formation of ARS-independent miniplasmids upon transformation of yeast Pichia methanolica with DNA molecules containing "transforming" and "nontransforming" genes].
In the study of transforming DNA molecules in cells of the methylotrophic yeast Pichia methanolica, it was found that the efficiency of transformation and the possibility of autonomous replication of hybrid plasmids and miniplasmids consisting of only transforming gene (Trg) sequences do not depend on the presence of ARS sequences with the canonical structure, such as 2 microns DNA in the yeast Saccharomyces cerevisiae. Data supported a suggestion about the existence of the relationship between gene transforming activity, its replicative ability, and transcription. The efficiency of vector activity of Trg is not sufficient to provide the transformation of other sequences of transforming DNA (tDNA). The loss of nonselected sequences of tDNA observed upon transformation is the result of rearrangements and deletions and is associated with the activity of cellular systems involved in nucleic acid metabolism. Miniplasmids similar in structure were shown to differ in their stability in independent transformants. The rate of loss of autonomously replicating plasmids strongly varied (from 1 to 99%) under nonselective conditions and nearly did not depend on plasmid structure.
Tarutina
M G
MG
State Research Institute of Genetics and Selection of Industrial Microorganisms, Moscow, 113545 Russia.
Tolstorukov
I I
II
D004261:DNA Replication; D004271:DNA, Fungal / Q000235:genetics* / Q000378:metabolism; D005800:Genes, Fungal; D005822:Genetic Vectors / Q000235:genetics; D010843:Pichia / Q000235:genetics*; D010957:Plasmids / Q000235:genetics* / Q000378:metabolism; D018741:Replication Origin; D012441:Saccharomyces cerevisiae / Q000235:genetics; D012641:Selection, Genetic; D014170:Transformation, Genetic / Q000235:genetics*
D004271:DNA, Fungal