This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend 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 CrossRef Citing Articles via Google Scholar Google Scholar Articles by Waterborg, J. H. Articles by Winicov, I. Search for Related Content PubMed PubMed Citation Articles by Waterborg, J. H. Articles by Winicov, I. Agricola Articles by Waterborg, J. H. Articles by Winicov, I.

Environmental and Stress Physiology

Differential Histone Acetylation in Alfalfa (Medicago sativa) Due to Growth in NaCl ¹

Responses in Salt Stressed and Salt Tolerant Callus Cultures

Department of Biochemistry, University of Nevada Reno, Reno, Nevada 89557

The steady state distribution of histone variant proteins and their modifications by acetylation were characterized in wild type and salinity stress adapted alfalfa (Medicago sativa). Isotopic labeling detected dynamic acetylation at four sites in the histone H3 variants and five sites in histones H4 and H2B. Histone variant H3.2 was the most highly acetylated histone with 25% higher steady state acetylation and a two- to threefold higher acetylation labeling than histone H3.1. Histone phosphorylation was limited to histone variants H1.A, H1.B, and H1.C and to histone H2A.3, which was also acetylated. Histone variant composition was unaffected by cellular exposure to NaCl. Histone acetylation was qualitatively similar in salt-tolerant and salt-sensitive cells under normal growth conditions. However, short term salt stress in salt sensitive cells or continued growth at 1% NaCl in salt tolerant cells led to major increases in the multiacetylated forms of histone H4 and the two variants of histone H3. These changes were more pronounced in the diploid than in the tetraploid alfalfa strains. The increase in multiacetylation of core histones serves as an in vivo reporter suggesting an altered intranuclear ionic environment in the presence of salt. It may also represent an adaptive response in chromatin structure to permit chromatin function in a more saline intranuclear environment.

¹ Supported in part by funds made available through Component 2, Nevada EPSCoR program of the National Science Foundation to the University of Nevada (I. W., J. H. W.), by U.S. Public Health Service grant GM 33435 (R. E. H.), and by Hatch Projects 131 (R. E. H.) and 103 (I. W.) from the college of Agriculture, University of Nevada Reno.

This article has been cited by other articles:

				J. H. Waterborg Steady-state Levels of Histone Acetylation in Saccharomyces cerevisiae J. Biol. Chem., April 21, 2000; 275(17): 13007 - 13011. [Abstract] [Full Text] [PDF]