Banding human chromosomes using a combined C-banding-fluorochrome staining technique.
Slides pretreated for C-banding and stained with DAPI or CMA3 show different banding patterns in human metaphase chromosomes compared to those obtained with either standard Giemsa C-banding or fluorochrome staining alone. Human chromosomes show C-plus DA-DAPI banding after C-banding plus DAPI and enhanced R-banding after C-banding plus Chromomycin A3 staining. If C-banding preferentially removes certain classes of DNA and proteins from different chromosome domains, C-banding pretreatment may cause a differential DNA extraction from G- and R-bands in human chromosomes, resulting in a preferential extraction of DNA included in G-bands. This hypothesis is partially supported by the selective cleavage and removal of DNA from R-bands of restriction endonuclease HaeIII with C-banding combined with DAPI or Chromomycin A3 staining. Structural factors relating to regional differences in DNA and/or proteins could also explain these results.
Bella
J L
JL
Department of Biology, School of Sciences, Autonomous University of Madrid, Spain.
Gosálvez
J
J
D002503:Centromere / Q000737:chemistry; D014128:Chromomycin A3; D002871:Chromosome Banding / Q000379:methods*; D002877:Chromosomes, Human; D005453:Fluorescence; D005456:Fluorescent Dyes; D006570:Heterochromatin / Q000737:chemistry; D006801:Humans; D007211:Indoles; D008214:Lymphocytes / Q000648:ultrastructure; D008677:Metaphase; D013194:Staining and Labeling / Q000379:methods; D014998:Y Chromosome
D005456:Fluorescent Dyes; D006570:Heterochromatin; D007211:Indoles; C007293:DAPI; D014128:Chromomycin A3