title: SAD-3, a Putative Helicase Required for Meiotic Silencing by Unpaired DNA, Interacts with Other Components of the Silencing Machinery.
abstract: In Neurospora crassa, genes lacking a pairing partner during meiosis are suppressed by a process known as meiotic silencing by unpaired DNA (MSUD). To identify novel MSUD components, we have developed a high-throughput reverse-genetic screen for use with the N. crassa knockout library. Here we describe the screening method and the characterization of a gene (sad-3) subsequently discovered. SAD-3 is a putative helicase required for MSUD and sexual spore production. It exists in a complex with other known MSUD proteins in the perinuclear region, a center for meiotic silencing activity. Orthologs of SAD-3 include Schizosaccharomyces pombe Hrr1, a helicase required for RNAi-induced heterochromatin formation. Both SAD-3 and Hrr1 interact with an RNA-directed RNA polymerase and an Argonaute, suggesting that certain aspects of silencing complex formation may be conserved between the two fungal species.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Hammond
authors.forename: Hua
authors.initials: H
authors.lastname: Xiao
authors.forename: Erin C
authors.initials: EC
authors.lastname: Boone
authors.forename: Tony D
authors.initials: TD
authors.lastname: Perdue
authors.forename: Patricia J
authors.initials: PJ
authors.lastname: Pukkila
authors.forename: Patrick K T
authors.initials: PK
authors.lastname: Shiu