Abstract: Our bodies consist of billions of genetically identical cells that can exhibit distinct phenotypic or epigenetic states. The covalent and reversible modification of histones enables cells to establish heritable gene expression patterns without altering their genetic blueprint. Epigenetic mechanisms that control gene expression are essential to maintain cellular identity and program multicellular differentiation. Histone H3 lysine 9 methylation (H3K9me) is associated with transcription silencing and heterochromatin formation. Fission yeast (S. pombe) has a minimalist heterochromatin architecture that is amenable to high-throughput genetics and biochemistry. A trio of conserved proteins regulates heterochromatin, which includes, 1) an H3K9me specific ''writer,'' Clr4Suv39h that catalyzes H3K9me 2) an H3K9me specific ''reader,'' Swi6HP1 that binds to H3K9me chromatin and silences transcription and, 3) an H3K9me specific ''eraser,'' Epe1JmjC, that opposes heterochromatin assembly and epigenetic inheritance. Fusing Clr4 to the tetracycline-inducible TetR DNA binding domain facilitates rapid and reversible control of heterochromatin assembly. My lab’s innovative genetic strategy has enabled us to identify chromatin-associated factors with unique roles that are restricted to heterochromatin maintenance. During the summer research experience supported by the supplement award, the undergraduate student will focus on generating new protein variants using a PCR based mutagenesis approach to identify alleles that enhance or suppress epigenetic inheritance. The research experience is designed to promote the technical, operation and professional skills of the candidate. The research experience is also aligned with the candidate’s future career aspirations to be a part of the biomedical workforce and pursue a graduate education. Furthermore,all of the scientific goals described here are fully consistent with the proposed research directions of the parent award.