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The organization of the ribosomal DNA (rDNA) repeat unit in the standard wild-type strain of Neurospora crassa, 74-OR23-1A, and in 30 other wild-type strains and wild-collected strains of N. crassa, . tetrasperma, N. sitophila, N. intermedia, and N. discreta isolated from nature, was investigated by restriction enzyme digestion of genomic DNA, and probing of the Southern-blotted DNA fragments with specific cloned pieces of the rDNA unit from 74-OR23-1A. The size of the rDNA unit in 74-OR23-1A was shown to be 9.20 kilobase pairs (kb) from blotting data, and the average for all strains was 9.11 + 0.21 kb; standard error = 0.038; coefficient of variation (C.V.) = 2.34%. These data indicate that the rDNA repeat unit size has been highly conserved among the Neurospora strains investigated. However, while all strains have a conserved HindIII site near the 5' end of the 25 S rDNA coding sequence, a polymorphism in the number and/or position of HindIII sites in the nontranscribed spacer region was found between strains. The 74-OR23-1A strain has two HindIII sites in the spacer, while others have from 0 to at least 3. This restriction site polymorphism is strain-specific and not species-specific. It was confirmed for some strains by restriction analysis of clones containing most of the rDNA repeat unit. The current restriction map of the 74-OR23-1A rDNA repeat unit is presented.
P J Russell, and
S Wagner, and
K D Rodland, and
R L Feinbaum, and
J P Russell, and
M S Bret-Harte, and
S J Free, and
R L Metzenberg
August 1976,
Journal of bacteriology,
P J Russell, and
S Wagner, and
K D Rodland, and
R L Feinbaum, and
J P Russell, and
M S Bret-Harte, and
S J Free, and
R L Metzenberg
November 1967,
Journal of bacteriology,
P J Russell, and
S Wagner, and
K D Rodland, and
R L Feinbaum, and
J P Russell, and
M S Bret-Harte, and
S J Free, and
R L Metzenberg
November 1979,
Journal of bacteriology,
P J Russell, and
S Wagner, and
K D Rodland, and
R L Feinbaum, and
J P Russell, and
M S Bret-Harte, and
S J Free, and
R L Metzenberg
November 1975,
Journal of bacteriology,
P J Russell, and
S Wagner, and
K D Rodland, and
R L Feinbaum, and
J P Russell, and
M S Bret-Harte, and
S J Free, and
R L Metzenberg
January 1973,
Biochemical Society symposium,
P J Russell, and
S Wagner, and
K D Rodland, and
R L Feinbaum, and
J P Russell, and
M S Bret-Harte, and
S J Free, and
R L Metzenberg
September 1972,
The Biochemical journal,
P J Russell, and
S Wagner, and
K D Rodland, and
R L Feinbaum, and
J P Russell, and
M S Bret-Harte, and
S J Free, and
R L Metzenberg
March 1979,
Journal of bacteriology,
P J Russell, and
S Wagner, and
K D Rodland, and
R L Feinbaum, and
J P Russell, and
M S Bret-Harte, and
S J Free, and
R L Metzenberg
August 1972,
The Biochemical journal,
P J Russell, and
S Wagner, and
K D Rodland, and
R L Feinbaum, and
J P Russell, and
M S Bret-Harte, and
S J Free, and
R L Metzenberg
June 1976,
Evolution; international journal of organic evolution,
P J Russell, and
S Wagner, and
K D Rodland, and
R L Feinbaum, and
J P Russell, and
M S Bret-Harte, and
S J Free, and
R L Metzenberg
January 1978,
Biochemical Society transactions,
