Characterization of aLycopersicon esculentumxSolanum lycopersicoidessomatic hybrid lacking a glutamate oxaloacetate transaminase isozyme
✍ Scribed by P. P. Moore; K. C. Sink
- Publisher
- Springer
- Year
- 1988
- Tongue
- English
- Weight
- 978 KB
- Volume
- 13
- Category
- Article
- ISSN
- 0167-6857
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✦ Synopsis
Morphological, cytological, isozyme and chloroplast DNA analyses were used to determine possible mechanism(s) for the loss of glutamate oxaloacetate transaminase-4 (GOT-4) isozyme activity in a somatic hybrid. Plant 204-1, derived by cell fusion between tomato (Lycopersicon esculentum) and Solanum lycopersicoides, was characterized for both Got-4 and acid phosphatase-2 (Aps-2), two isozyme loci which are closely linked (recombination 2.5 cM). This hybrid was determined to be chimeric for both Got-4 and Aps-2. The S. lycopersicoides plant used to provide cells for the fusion was determined to be heterozygous for both Got-4 and Aps-2. Only one S. lycopersicoides allelic form of Aps-2 and Got-4 was found in plant 204-1. This observation indicated that either the alternative copy of the S. lycopersicoides chromosome region encoding Got-4 and Aps-2 is deleted or the entire chromosome is absent.
Plant 204-1 was cytologically determined to be aneuploid with approximately 62 chromosomes. Sixty-two somatic hybrids of separate callus origin were analysed for GOT-4 and a high proportion (27 %) lacked the S. lycopersicoides form of Got-4. The loss of this allele and the linked Aps allele most likely occurred in the suspension culture of S. lycopersicoides used to provide cells for fusion.