Proteins and Genes Preferentially Expressed in the Cultured Cells of Interspecific Hybrid of Genus Nicotiana (N. gossei x N. tabacum) Which Die of Hybrid Lethality

Abstract

A cultured cell line, GTH4 (N. gossei x N. tabacum), which exhibits hybrid lethality, dies at 26C, but not at 37C. However, GTH4S, a variant cell line derived from GTH4 does not die at 26C. Both gene expression and protein synthesis at 37C are prerequisite for cell death of GTH4, suggesting that those are absent in GHT4S. We compared protein profiles of GTH4 to GTH4S by ion-exchange chromatography/SDS-PAGE and MALDI-TOF MS, found that Annexin (AY14973) involved in cell cycle was present in GTH4 but absent in GTH4S. The RT-PCR analysis showed that transcript of this Annexin gene was totally missing in GTH4S, supporting the results of protein analysis. Transcription of other Annexin genes (AY965682, AY965683) that respond to biotic/abiotic stresses was reduced in GTH4S cells. In relationship to those results, profiles of the genes preferentially expressed in GTH4 will be also discussed.