A new Solanum satellite DNA containing species-specific sequences which can be used for identification of genome parts in somatic hybrids of potato.

摘要

After PCR amplification, complete 337-bp repeats of a satellite DNA component of S. demissum were cloned and subsequently sequenced (pSDB6). This satellite was initially detected by hybridization of Solanum DNA with a short clone, pSDT382, previously cloned from S. demissum and described as species-specific for some wild Solanum species and potato breeding lines. Within the sequence of pSDB6, a high similarity (77%) was detected to a 75-bp region of a common Solanum-specific repeat (pSA287; 183 bpin length). It is suggested that the species-specificity is restricted to a short region within the 337-bp element. This new element appeared to be present in S. okadae, S. kurtzianum, S. maglia, S. acaule and S. demissum (belonging to different series of potato) and was also detected by Southern blot analysis in some S. tuberosum breeding lines. It is suggested that the short clone pSDT382 can be used to detect specific genome parts of species such as S. okadae, S. kurtzianum and S. maglia in symmetricsomatic hybrids obtained by protoplast fusion with selected S. tuberosum breeding lines not containing this repeat type. Evolution of satellite DNA within Solanum/Lycopersicon species is discussed. Nucleotide sequence data have been submitted to the EMBL database under the accession number Y08906.