Chromosomal localization and sequence variation of 5S rRNA gene in five Capsicum species

Chromosomal localization and sequence analysis of the 5S rRNA gene were car ried out in five Capsicum species. Fluorescence in situ hybridization revea led that chromosomal location of the 5S rRNA gene was conserved in a single locus at a chromosome which was assigned to chromosome 1 by the synteny re lationship with tomato. In sequence analysis, the repeating units of the 5S rRNA genes in the Capsicum species were variable in size from 278 bp to 30 0 bp, In sequence comparison of our results to the results with other Solan aceae plants as published by others, the coding region was highly conserved , but the spacer regions varied in size and sequence, T stretch regions, ju st after the end of the coding sequences, were more prominant in the Capsic um species than in two other plants, High G.C rich regions, which might hav e similar functions as that of the GC islands in the genes transcribed by R NA PolII, were observed after the T stretch region. Although we could not o bserve the TATA like sequences, an AT rich segment at -27 to -18 was detect ed in the 5S rRNA genes of the Capsicum species. Species relationship among the Capsicum species was also studied by the sequence comparison of the 5S rRNA genes, While C. chinense, C. frutescens, and C. annuum formed one lin eage, C. baccatum was revealed to be an intermediate species between the fo rmer three species and C. pubescens.