Open AccessHow to stain nucleic acids and proteins in Miller spreads
Author(s) -
Lorena Zannino,
Marco Biggiogera
Publication year - 2022
Publication title -
european journal of histochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.754
H-Index - 42
eISSN - 2038-8306
pISSN - 1121-760X
DOI - 10.4081/ejh.2022.3364
Subject(s) - staining , nucleic acid , uranyl acetate , stain , osmium , chemistry , osmium tetroxide , chromatin , dna , biochemistry , microbiology and biotechnology , electron microscope , biology , genetics , physics , ruthenium , optics , catalysis
The spread technique proposed by Miller and Beatty in 1969 allowed for the first time the visualization at transmission electron microscopy of nucleic acids and chromatin in an isolated and distended conformation. The final step of staining the spread chromatin is of critical importance because it can strongly influence the interpretation of the results. We evaluated different staining techniques and the most part of them provided a good result. Specifically, well contrasted micrographs were obtained when staining with H3PW12O40 (PTA), as originally proposed by Miller and Beatty, and with two alternatives proposed here: uranyl acetate or terbium citrate staining. Quite good contrast of the spread DNA could be achieved also by using Osmium Ammine; while no or few contrast of nucleic acids was observed by staining with KMnO₄ and H3PMo12O40 (PMA) respectively.