Luense, Lacey Assistant Professor

Dr. Luense's research focus is understating the epigenetic regulation of the paternal genome, how it directly affects male fertility, and how it ultimately influences embryonic development and developmental programming. The paternal epigenome is likely to be a key mechanistic driver of male infertility, largely due to the unique chromatin organization of mammalian sperm that is achieved by replacing over 90% of nucleosomes (composed of histone proteins) with protamines. During this process the male germ cell undergoes histone hyperacetylation to "loosen" and open the chromatin structure leading to subsequent eviction of nucleosomes. The location of retained nucleosomes in sperm remains unclear, with several genomic sequencing studies pointing to different locations. Importantly, abnormal nucleosome retention and protamine insufficiency are correlated with male infertility, although the underlying mechanism - whether this is due to excess histones or aberrantly packaged DNA - has not yet been elucidated. Thus, in spite of its likely profound importance, the requirement and role of specific nucleosome retention is still poorly understood and remains to be explicitly tested.