FISH-mapping of the 5S rDNA locus in chili peppers (Capsicum-Solanaceae)

Abstract

We present here the physical mapping of the 5S rDNA locus in six wild and fi ve cultivated taxa of Capsicum by means of a genus-specifi c FISH probe. In all taxa, a single 5S locus per haploid genome that persistently mapped onto the short arm of a unique metacentric chromosome pair at intercalar position, was found. 5S FISH signals of almost the same size and brightness intensity were observed in all the analyzed taxa. This is the fi rst cytological characterization of the 5S in wild taxa of Capsicum by using a genus-derived probe, and the most exhaustive and comprehensive in the chili peppers up to now. The information provided here will aid the cytomolecular characterization of pepper germplasm to evaluate variability and can be instrumental to integrate physical, genetic and genomic maps already generated in the genus.

Large-scale comparative analysis of cytogenetic markers across Lepidoptera

“…separated by long spacers varying both in size and sequence. Clusters of 5S rDNA genes have been successfully mapped in many taxa 38 , 42 , 97 , 98 . However, the presence of multiple loci, which remain undetected even by TSA-FISH, questions homology of detected clusters and the usefulness of this marker in studies on karyotype evolution.…”

IAPT/IOPB chromosome data 26

“…Chromosome pairs with ribosomal loci are numbered and those active NORs are pointed out with arrowheads; also note the light blue intercalar cHet block at pair no. 2 (asterisks) D, Idiogram; note that each chromosome of the complement can be identified by morphological and/or rDNA and cHet markers; position of 5S rDNA follows to Aguilera & al. (2016) A.…”

An Integrated Physical Map of the Cultivated Hot Chili Pepper, Capsicum baccatum var. Pendulum

“…The number and the interstitial position of the 5S locus are conserved throughout chili peppers (Aguilera et al, 2016). The 5S rDNA locus in our plant material in fact colocalizes with an intercalar constitutive heterochromatic CMA + band at p5 of distinct accesions of C. baccatum var.…”

“…Nucleotide sequence data and supplementary information are available at the NCBI under the accession numbers FJ460246, FJ460247, JF766708, JF766709, JF766710 and JF766711. Furthermore, the production of the 5S rDNA Capsicumderived probe (0.3 Kbp) for FISH is detailed in Aguilera et al (2016). FISH experiments were undertaken according to Moscone et al (1996b).…”