This Article Full Text Full Text (PDF) All Versions of this Article: jhc.5A6725.2005v1 54/3/301    most recent Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Rait, V. K. Articles by O'Leary, T. J. Search for Related Content PubMed PubMed Citation Articles by Rait, V. K. Articles by O'Leary, T. J. Social Bookmarking                      What's this?

Conversions of Formaldehyde-modified 2'-Deoxyadenosine 5'-Monophosphate in Conditions Modeling Formalin-fixed Tissue Dehydration

Vladimir K. Rait, Qingrong Zhang, Daniele Fabris, Jeffrey T. Mason and Timothy J. O'Leary

Department of Biophysics, Armed Forces Institute of Pathology, Rockville, Maryland (VKR,JTM,TJO); Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore, Maryland (QZ,DF); and Biomedical Laboratory Research and Development Service, Veteran Health Administration, Washington, District of Columbia (TJO)

Correspondence to: Timothy J. O'Leary, Biomedical Laboratory R&D Service, Department of Veterans Affairs, 810 Vermont Avenue, NW, Washington, DC 20420. E-mail: timothy.oleary{at}va.gov

Formalin-fixed, paraffin-embedded specimens typically provide molecular biologists with low yields of extractable nucleic acids that exhibit extensive strand cleavage and covalent modification of nucleic acid bases. This study supports the idea that these deleterious effects are promoted by the first step in formalin-fixed tissue processing—i.e., tissue dehydration with a graded series of alcohols. We analyzed the conversions of formaldehyde-modified 2'-deoxyadenosine 5'-monophosphate (dAMP) by reverse-phase ion-pair, high-performance liquid chromatography and found that dehydration does not stabilize N-methylol groups in the modified nucleotide. Furthermore, spontaneous demodification in a dry state or in anhydrous ethanol can be as fast as it is in aqueous solutions if the preparation is contaminated with salts of orthophosphoric acid. In ethanol, orthophosphates also catalyze formation of abundant N⁶-ethoxymethyl-dAMP, as well as cross-linking and depurination of nucleotides present in the mixture. Identification of the products was performed using ultraviolet absorbance spectroscopy and electrospray ionization Fourier-transform ion cyclotron resonance mass spectrometry. Alternatives to the traditional processing of formalin-fixed tissues are discussed. (J Histochem Cytochem 54:301–310, 2006)

Key Words: formalin fixation • dAMP • mixed acetals • crosslinking • depurination • HPLC • ESI FTICR MS

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				M. S. Scicchitano, D. A. Dalmas, M. A. Bertiaux, S. M. Anderson, L. R. Turner, R. A. Thomas, R. Mirable, and R. W. Boyce Preliminary Comparison of Quantity, Quality, and Microarray Performance of RNA Extracted From Formalin-fixed, Paraffin-embedded, and Unfixed Frozen Tissue Samples J. Histochem. Cytochem., November 1, 2006; 54(11): 1229 - 1237. [Abstract] [Full Text] [PDF]

Guidelines | Subscriptions | About | exPRESS - Current - Archive | Business Information | Contact

The Journal of Histochemistry & Cytochemistry is owned, published, and licensed by The Histochemical Society © 2006