@entity1460 ( @entity1460 ) is the only known higher plant with a definitely established occurrence of somatic crossing over. This material lends itself to the analysis of somatic crossing over, gross chromosomal aberrations and mutations, all of which may be induced by the same treatment of the mutagen given to seeds. This is made possible because gene Y(11) for @entity38 development in the variety L65-1237 is incompletely dominant over its allele y(11), so that twin or double spots composed of a dark green (Y(11)Y(11)) and a yellow (y(11)y(11)) component can be observed adjacent to and as mirror images of each other on the light green Y(11)y(11) leaves in the areas of complementary exchange for these genes. Lack of growth of either component of this double spot as well as several types of chromosomal disturbances give rise to single spots resembling phenotypes of y(11)y(11) or Y(11)Y(11) leaves. Point mutations can be studied by looking for green sectors originating from Y(11)y(11) genotype on the y(11)y(11) plants. Seeds obtained from heterozygous plants were treated with @entity5834 , @entity2592 , @entity4316 and @entity10049 , all known inhibitors of DNA synthesis, and @entity5808 , an inhibitor of synthesis of proteins. The treatments with @entity5834 and @entity4316 increased the frequency of somatic crossing over as measured by the frequency of double spots on Y(11)y(11) leaves, but @entity2592 , @entity10049 and @entity5808 did not. Thus somatic crossing over was induced only by those chemicals which are known to allow rejoining of chromosomes, thereby suggesting a correlation between the two phenomena. These observations indicate that it is not the mere inhibition of DNA synthesis, but some rather more specific event in DNA repair which is responsible for complementary exchanges. Some of these results differ from studies carried out with fungi. The main effect of all chemicals tested, except @entity5834 and @entity4316 , was inferred to be the production of deletions in Y(11)y(11) plants which raised the frequency of single (dark green or yellow) spots relative to the doubles. @entity5834 was the only chemical which constantly increased the frequency of specific point mutations. In the control material, the great majority of spots are found on the upper surface of the leaf. This picture could not be changed in any of the treated materials, thus indicating uniform resistance of spongy mesophyll tissue to the mutagens applied.

Somatic Crossing over in XXXX (L.) Merrill: Effect of Some Inhibitors of DNA Synthesis on the Induction of Somatic Crossing over and Point Mutations.

@entity5808 :: ('MESH:D011691', 'Chemical') :: ['puromycin'] @entity5834 :: ('MESH:D002110', 'Chemical') :: ['caffeine', 'Caffeine'] @entity10049 :: ('MESH:D005467', 'Chemical') :: ['5-fluorodeoxyuridine', '5-fluoro-deoxyuridine'] @entity4316 :: ('MESH:D003609', 'Chemical') :: ['actinomycin D'] @entity2592 :: ('MESH:D003561', 'Chemical') :: ['cytosine arabinoside'] @entity1460 :: ('3847', 'Species') :: ['soybean', 'Glycine max'] @entity38 :: ('MESH:D002734', 'Chemical') :: ['chlorophyll']
@entity1460 :: (3847,Species) :: ['GLYCINE MAX']
