home > TRiO and USP Programs > McNair > symposium > 2008 presentations > Francis Maddox

Francis Maddox
Biology

Eric Selker, Mentor
Keyur Adhvaryu, Mentor

Characterization of Histone H4 N-Terminal Regulation of DNA Methylation in Neurospora Crassa

The regulation of genomic expression in eukaryotes is accomplished by a variety of cellular mechanisms which may activate or silence specific genes. DNA methylation, an expression regulator often associated with genetic silencing, is particularly interesting because patterns of methylation related to such processes as histone modification are being actively researched. Recent investigations indicate the possibility that the n-terminal tails of core histones, around which DNA is packaged into the nucleosome, play some role in regulating methylation. This study indicates to what extent the H4 n-terminal residues are interrelated with the process of localized and global methylation. Such correlations are identified by substituting each of twenty-one modifications of the gene encoding histone H4 for that same gene in a suitable strain of Neurospora Crassa. Patterns of methylation and phenotypic variance in the tested H4 strains indicate to what extent the structure of H4 is involved in DNA methylation.