Ribosomal DNA localization on Lathyrus species chromosomes by FISH

Abstract

Background Fluorescence In Situ Hybridization (FISH) played an essential role to locate the ribosomal RNA genes on the chromosomes that offered a new tool to study the chromosome structure and evolution in plant. The 45S and 5S rRNA genes are independent and localized at one or more loci per the chromosome complement, their positions along chromosomes offer useful markers for chromosome discriminations. In the current study FISH has been performed to locate 45S and 5S rRNA genes on the chromosomes of nine Lathyrus species belong to five different sections, all have chromosome number 2n=14, Lathyrus gorgoni Parl, Lathyrus hirsutus L., Lathyrus amphicarpos L., Lathyrus odoratus L., Lathyrus sphaericus Retz, Lathyrus incospicuus L, Lathyrus paranensis Burkart, Lathyrus nissolia L., and Lathyrus articulates L. Results The revealed loci of 45S and 5S rDNA by FISH on metaphase chromosomes of the examined species were as follow: all of the studied species have one 45S rDNA locus and one 5S rDNA locus except L. odoratus L., L. amphicarpos L. and L. sphaericus Retz L. have two loci of 5S rDNA. Three out of the nine examined species have the loci of 45S and 5S rRNA genes on the opposite arms of the same chromosome (L. nissolia L., L. amphicarpos L., and L. incospicuus L.), while L. hirsutus L. has both loci on the same chromosome arm. The other five species showed the loci of the two types of rDNA on different chromosomes. Conclusion The detected 5S and 45S rDNA loci in Lathyrus could be used as chromosomal markers to discriminate the chromosome pairs of the examined species. FISH could discriminate only one chromosome pair out of the seven pairs in three species, in L. hirsutus L., L. nissolia L. and L. incospicuus L., and two chromosome pairs in five species, in L. paranensis Burkart, L. odoratus L., L. amphicarpos L., L. gorgoni Parl. and L. articulatus L., while it could discriminate three chromosome pairs in L. sphaericus Retz. these results could contribute into the physical genome mapping of Lathyrus species and the evolution of rDNA patterns by FISH in the coming studies in future.

Crop Wild Relatives (CWR) Priority in Italy: Distribution, Ecology, In Situ and Ex Situ Conservation and Expected Actions

“…These data, combined with the benefits attributable to the secondary metabolites (polyphenol contents), suggests the use of the genus Lathyrus, and in particular of L. amphicarpos, in human and animal diets [162]. L. palustris also has favorable histological characteristics for use as a fodder crop [154,163].…”

“…L. palustris is a perennial plant and natural autohexaploid, having 2 n = 6× = 42 chromosome [153], while L. amphicarpos has a 2 n = 14 chromosome [154].…”

Crop Wild Relatives (CWR) Priority in Italy: Distribution, Ecology, In situ and Ex situ Conservation and Expected Actions

“…L. palustris is a perennial plant and natural autohexaploid, having 2n=6x=42 [144], while L. amphicarpos has 2n=14 [145].…”

“…This data combined with the benefits attributable to the secondary metabolites (polyphenol contents), suggests the use of the genus Lathyrus, and in particular of L. amphicarpos in human and animal diet [153]. L. palustris has also favorable histological characteristics for use as fodder crop [145,154].…”