title: Trans-Homolog Interactions Facilitating Paramutation in Maize.
abstract: Paramutations represent locus-specific trans-homolog interactions affecting the heritable silencing properties of endogenous alleles. Although examples of paramutation are well studied in maize (Zea mays), the responsible mechanisms remain unclear. Genetic analyses indicate roles for plant-specific DNA-dependent RNA polymerases that generate small RNAs, and current working models hypothesize that these small RNAs direct heritable changes at sequences often acting as transcriptional enhancers. Several studies have defined specific sequences that mediate paramutation behaviors, and recent results identify a diversity of DNA-dependent RNA polymerase complexes operating in maize. Other reports ascribe broader roles for some of these complexes in normal genome function. This review highlights recent research to understand the molecular mechanisms of paramutation and examines evidence relevant to small RNA-based modes of transgenerational epigenetic inheritance.
authors.affiliation: Department of Molecular Genetics, Center for RNA Biology, Ohio State University, Columbus, Ohio 43210.
authors.forename: Brian John
authors.identifier: http://orcid.org/0000-0001-9846-3473
authors.initials: BJ
authors.lastname: Giacopelli
authors.affiliation: Department of Molecular Genetics, Center for RNA Biology, Ohio State University, Columbus, Ohio 43210 hollick.3@osu.edu.
authors.forename: Jay Brian
authors.identifier: http://orcid.org/0000-0001-9250-4836
authors.initials: JB
authors.lastname: Hollick
mesh_terms: D000483:Alleles; D012321:DNA-Directed RNA Polymerases / Q000235:genetics*; D004742:Enhancer Elements, Genetic; D044127:Epigenesis, Genetic; D018506:Gene Expression Regulation, Plant; D009154:Mutation; D010940:Plant Proteins / Q000235:genetics; D018749:RNA, Plant / Q000235:genetics; D012045:Regulatory Sequences, Nucleic Acid; D003313:Zea mays / Q000235:genetics*
chemical_list: D010940:Plant Proteins; D018749:RNA, Plant; D012321:DNA-Directed RNA Polymerases