Molecular heterosis for heat-sensitive enzyme alleles.
نویسندگان
چکیده
Heat denaturation studies were carried out and revealed hidden genic variants with the same net charge at the Octanol dehydrogenase-1 locus in Drosophila pseudoobscura. Studies of several genetic crosses between strains with different heat-sensitivity alleles showed that the F(1) retained more in vitro enzyme activity after being heat-treated for a specified amount of time at a given temperature than the heat-resistant parent. We call this phenomenon "heterosis for heat-stability of enzyme activity" and discuss its possible molecular mechanism, its relation to maintenance of genetic variation in natural populations, and its bearing on the "classical" and "balance" hypotheses.
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 71 5 شماره
صفحات -
تاریخ انتشار 1974