Physical Mapping of Ribosomal DNA Genes on <i>Jatropha curcas</i> Chromosomes by Multicolor FISH

Abstract

Summary Jatropha curcas L. belonging to the Euphorbiaceae is becoming a significant crop in tropical areas nowadays. The genetic diversity among 1 African and 5 Asian varieties were analyzed by multicolor fluorescence in situ hybridization (McFISH) using 5S and 45S ribosomal RNA genes (rDNAs). One locus of 5S rDNA and 2 loci for 45S rDNA were detected at specific regions of the chromosomes in all the materials. Also, telomeric repeats (TTTAGGG) n were localized on the terminal regions of all chromosomes. The present results confirm the stability of these major repeated sequences among Jatropha lines.

Unraveling the karyotype structure of the spurges Euphorbia hirta Linnaeus, 1753 and E. hyssopifolia Linnaeus, 1753 (Euphorbiaceae) using genome size estimation and heterochromatin differentiation

“…On the other hand, only one site of 5S rDNA was observed in an interstitial position of the short arm of chromosome pair 2 of Euphorbia hirta (Figure 1I) and pair 1 of Euphorbia hyssopifolia (Figure 2I), as described for all other karyotypes within the family (Leitch et al 1998, Carvalho and Guerra 2002, Witkowska et al 2009, Vasconcelos et al 2010). In addition, both species presented 5S rDNA sites associated with CMA + bands (Figure 3), as described for castor, in which there was also a chromosome pair bearing both 5S rDNA and 45S rDNA (Vasconcelos et al 2010), and other few angiosperms (e.g.…”

Conservation and Variation of 35S Ribosomal DNA among Five <i>Jatropha</i> Species Revealed by Fluorescence <i>In Situ</i> Hybridization

“…Although karyotyping and fluorescence in situ hybridization (FISH) mapping of DNA repeats have been used to cytologically characterize J. curcas (Carvalho et al 2008, Witkowska et al 2009, Kikuchi et al 2011, Alipour et al 2013, Gong et al 2013 and its whole genome has been sequenced (Sato et al 2011, Hirakawa et al 2012, Wu et al 2015, cytological information on other Jatropha species is limited. FISH analysis using rDNAs is a powerful technique for karyotype analysis (Leitch and Heslop-Harrison 1992, Kikuchi et al 2006, Kikuchi et al 2008, Garcia et al 2012.…”

“…FISH analysis using rDNAs is a powerful technique for karyotype analysis (Leitch and Heslop-Harrison 1992, Kikuchi et al 2006, Kikuchi et al 2008, Garcia et al 2012. Among Jatropha species, it has been used only in J. curcas accessions and has revealed one locus of 5S and two loci of 35S (18S-5.8S-26S) rDNA in each accession (Witkowska et al 2009, Gong et al 2013.…”

Jatropha curcas: a review on biotechnological status and challenges

“…Improved molecular cytogenetic techniques have not been applied extensively to determine phylogenetic relationship at the species and cultivar level. Molecular cytogenetical studies using techniques like multicolour FISH used by Witkowska et al (2009) will further help in interspecific characterization of J. curcas. Recent extensive research on plant chromosomes has moved the chromosome from a minor position in biological research to a position where many researchers consider the chromosome as one of the major targets of biological study, especially in the fields of biotechnology and life sciences.…”

“…Recent extensive research on plant chromosomes has moved the chromosome from a minor position in biological research to a position where many researchers consider the chromosome as one of the major targets of biological study, especially in the fields of biotechnology and life sciences. To sum up, chromosome number, size, morphology, preparation and staining techniques (Mukherjee and Jha, personal communication) the small genome size (Carvalho et al 2008) and initial success in molecular cytogenetics (Witkowska et al 2009) are favorable features for the entry of the new crop J. curcas in the biotechnology era.…”