<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zoldos, V</style></author><author><style face="normal" font="default" size="100%">Papes, D</style></author><author><style face="normal" font="default" size="100%">Cerbah, M</style></author><author><style face="normal" font="default" size="100%">Panaud, O</style></author><author><style face="normal" font="default" size="100%">Besendorfer, V</style></author><author><style face="normal" font="default" size="100%">Siljak-Yakovlev, S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Molecular-cytogenetic studies of ribosomal genes and heterochromatin reveal conserved genome organization among 11 Quercus species</style></title><secondary-title><style face="normal" font="default" size="100%">TAG Theoretical and Applied Genetics</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">18S-5.8S-26 S and 5 S rRNA genes</style></keyword><keyword><style  face="normal" font="default" size="100%">FISH</style></keyword><keyword><style  face="normal" font="default" size="100%">Fluorochrome banding</style></keyword><keyword><style  face="normal" font="default" size="100%">Heterochromatin</style></keyword><keyword><style  face="normal" font="default" size="100%">karyotype</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1999</style></year></dates><volume><style face="normal" font="default" size="100%">99</style></volume><pages><style face="normal" font="default" size="100%">969-977</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Genomes of 11 Quercus species were characterized using cytogenetic (Giemsa C-banding, fluorochrome banding), molecular-cytogenetic (fluorescence in situ hybridization, FISH, to ribosomal genes) and molecular (dot-blot for ribosomal gene-copy number assessment) techniques. Ribosomal genes are the first DNA sequences to be physically mapped in oaks, and the copy number of the 18S-5.8S-26 S rRNA genes is estimated for the first time. Oak karyotypes were analysed on the basis of DAPI banding and FISH patterns; five marker chromosomes were found. In addition, chromosomal organization of ribosomal genes with respect to AT- and GC-differentiated heterochromatin was studied. Fluorochrome staining produced very similar CMA/DAPI banding patterns, and the position and number of ribosomal loci were identical for all the species studied. The 18S-5.8S-26 S rRNA genes in oak complements were represented by a major locus at the subterminal secondary constriction (SC) of the only subtelocentric chromosome pair and a minor locus at paracentromeric SC of one metacentric pair. The only 5 S rDNA locus was revealed at the paracentromeric region of the second largest metacentric pair. A striking karyotypic similarity, shown by both fluorochrome banding and FISH patterns, implies close genome relationships among oak species no matter their geographic origin (European or American) or their ecophysiology (deciduous or evergreens). Dot-blot analysis gave preliminary evidence for different copy numbers of 18S-5.8S-26 S rRNA genes in diploid genomes of Q. cerris, Q. ilex, Q. petraea, Q. pubescens and Q. robur (2700, 1300, 2200, 4000 and 2200 copies, respectively) that was correlated with the size polymorphism of the major locus.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zoldo, V</style></author><author><style face="normal" font="default" size="100%">Pape, D</style></author><author><style face="normal" font="default" size="100%">Brown, S C</style></author><author><style face="normal" font="default" size="100%">Panaud, O</style></author><author><style face="normal" font="default" size="100%">Zoldos, V</style></author><author><style face="normal" font="default" size="100%">Papes, D</style></author><author><style face="normal" font="default" size="100%">Siljak-Yakovlev, S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome size and base composition of seven Quercus species: inter- and intra-population variation</style></title><secondary-title><style face="normal" font="default" size="100%">Genome</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">DNA content variations</style></keyword><keyword><style  face="normal" font="default" size="100%">extra chromosomes</style></keyword><keyword><style  face="normal" font="default" size="100%">flow cytometry</style></keyword><keyword><style  face="normal" font="default" size="100%">GC percent</style></keyword><keyword><style  face="normal" font="default" size="100%">genome size</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1998</style></year></dates><publisher><style face="normal" font="default" size="100%">NRC Research Press</style></publisher><volume><style face="normal" font="default" size="100%">41</style></volume><pages><style face="normal" font="default" size="100%">162-168</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Seven Quercus species, four deciduous (Q. cerris, Q. petraea, Q. pubescens, andQ. robur) and three evergreen (Q. coccifera, Q. ilex, andQ. suber), were assessed for DNA content. Their genome sizes ranged from 1.88 to 2.00 pg/2C, namely an interspecific DNA content variation of 6%. In addition, the DNA content of several populations of Q. petraea andQ. robur with different geographical origins, French and Croatian, was estimated. DNA content did not vary among four populations of Q. robur, but did differ between two populations of Q. petraea, the French population having a higher 2C DNA value than the Croatian. The genome size of this French population showed important dispersion among 10 measured individuals. This was in accordance with subsequent cytogenetic data that revealed extra chromosomes in some individuals from this population. The percent GC varied little between the species; a GC content of 39.9% is established as typical for oak.Key words: Quercus, flow cytometry, genome size, GC percent, DNA content variations, extra chromosomes.</style></abstract></record></records></xml>