MOLECULAR AND FUNCTIONAL CHARACTERIZATION OF S-RNAses FROM A NATURAL POPULATION OF Nicotiana alata

ROLDÁN, JA; QUIROGA, R; ROJAS, HJ; GOLDRAIJ, A

San Miguel de Tucumán, Tucumán , Argentina.

Congreso; XLV Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2009

SAIB

We report here the molecular and functional characterization ofnovel S-RNase candidates identified from a natural population ofNicotiana alata. Using degenerated oligonucleotides based onconserved domains of S-RNases, we identified by RT-PCR ten stylesequences homologous to S-RNases, including three previouslyreported functional S-RNases and seven novel S-RNase candidates.Six of these candidates showed, by allele-specific RT-PCR, plant-specific expression in the natural population and style specificamplification, which increased gradually during bud maturation,consistent with the reported S-RNase expression. In contrast, theS63 sequence was present in all plants examined and wasubiquitously expressed in different organs and bud developmentalstages. Genetic analysis confirmed the association with self-incompatible function in five S-RNase candidates while S5 and S63appeared to be nonfunctional relic S-RNases. Phylogeneticalanalysis showed the Nicotiana alata S-RNases were included ineight transgeneric lines confirming that this species represents abroad sample of allelic variation at the S-locus of the Solanaceae.