Characterization of two types of yeast ribosomal DNA genes

Abstract
The intragenic organization of rDNA from a diploid strain of Saccharomyces cerevisiae was analyzed by using recombinant DNA molecules constructed in vitro. Restriction analysis of the yeast ribosomal DNA with the EcoRI restriction enzyme indicated that 8 restriction fragments were present in the ribosomal DNA of this strain: X'' (1.87 .times. 106 daltons), A (1.77 .times. 106 daltons), B (1.48 .times. 106 daltons), C (1.22 .times. 106 daltons), D (0.39 .times. 106 daltons), E (0.36 .times. 106 daltons), F (0.22 .times. 106 daltons) and G (0.17 .times. 106 daltons). These fragments were distributed between 2 different types of ribosomal DNA genes.