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# On the nature of the polymorphism of the small subunit of ribulose-1,5-diphosphate carboxylase in the amphidiploid Nicotiana tabacum

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## Abstract

The N-terminal amino acid sequence of the small subunit of ribulose-1,5=disphosphate carboxylase from the amphidiploidNicotiana tabacum contains two polymorphisms. From examination of the equivalent sequences in the putative parent speciesNicotiana sylvestris andtomentosiformis it is concluded that the amphidiploidNicotiana tabacum has inherited two alleles for the small subunit of ribulose diphosphate carboxylase, one from each parent species. The alleles continue to be retained and expressed. The relevance of these findings is discussed in relation to the successful adaption of the amphidiploidNicotiana tabacum to a wide range of environments.
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... Nicotiana tabacum which is likely to be the result of a fusion of Nicotiana sylvestris and Nicotiana tomentosiformis (Strobaek et al. 1976). This type of duplication however, can give rise only to dispersed multi-gene families. ...
Chapter
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Chapter
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Chapter
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Article
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Chapter
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Chapter
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Article
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Article
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Article
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Article
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Article
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