title: RNA interference in the moss Physcomitrella patens.
abstract: The moss Physcomitrella patens performs efficient homologous recombination, which allows for the study of individual gene function by generating gene disruptions. Yet, if the gene of study is essential, gene disruptions cannot be isolated in the predominantly haploid P. patens. Additionally, disruption of a gene does not always generate observable phenotypes due to redundant functions from related genes. However, RNA interference (RNAi) can provide mutants for both of these situations. We show that RNAi disrupts gene expression in P. patens, adding a significant tool for the study of plant gene function. To assay for RNAi in moss, we constructed a line (NLS-4) expressing a nuclearly localized green fluorescent protein (GFP):beta-glucuronidase (GUS) fusion reporter protein. We targeted the reporter protein with two RNAi constructs, GUS-RNAi and GFP-RNAi, expressed transiently by particle bombardment. Transformed protonemal cells are marked by cobombardment with dsRed2, which diffuses between the nucleus and cytoplasm. Cells transformed with control constructs have nuclear/cytoplasmic red fluorescence and nuclear green fluorescence. In cells transformed with GUS-RNAi or GFP-RNAi constructs, the nuclear green fluorescence was reduced on average 9-fold as soon as 48 h after transformation. Moreover, isolated lines of NLS-4 stably transformed with GUS-RNAi construct have silenced nuclear GFP, indicating that RNAi is propagated stably. Thus, RNAi adds a powerful tool for functional analysis of plant genes in moss.
authors.affiliation: Department of Biology, Washington University, 1 Brookings Drive, Saint Louis, Missouri 63130-4899, USA. manena@biology.wustl.edu
authors.forename: Magdalena
authors.initials: M
authors.lastname: Bezanilla
authors.forename: Aihong
authors.initials: A
authors.lastname: Pan
authors.forename: Ralph S
authors.initials: RS
authors.lastname: Quatrano
mesh_terms: D019068:Bryopsida / Q000166:cytology / Q000235:genetics*; D003001:Cloning, Molecular; D049452:Green Fluorescent Proteins; D007091:Image Processing, Computer-Assisted; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000235:genetics; D018749:RNA, Plant / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014170:Transformation, Genetic
chemical_list: D008164:Luminescent Proteins; D018749:RNA, Plant; D034741:RNA, Small Interfering; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins