title: Phytophthora capsici homologue of the cell cycle regulator SDA1 is required for sporangial morphology, mycelial growth and plant infection.
abstract: SDA1 encodes a highly conserved protein that is widely distributed in eukaryotic organisms. SDA1 is essential for cell cycle progression and organization of the actin cytoskeleton in yeasts and humans. In this study, we identified a Phytophthora capsici orthologue of yeast SDA1, named PcSDA1. In P. capsici, PcSDA1 is strongly expressed in three asexual developmental states (mycelium, sporangia and germinating cysts), as well as late in infection. Silencing or overexpression of PcSDA1 in P. capsici transformants affected the growth of hyphae and sporangiophores, sporangial development, cyst germination and zoospore release. Phalloidin staining confirmed that PcSDA1 is required for organization of the actin cytoskeleton. Moreover, 4',6-diamidino-2-phenylindole (DAPI) staining and PcSDA1-green fluorescent protein (GFP) fusions revealed that PcSDA1 is involved in the regulation of nuclear distribution in hyphae and sporangia. Both silenced and overexpression transformants showed severely diminished virulence. Thus, our results suggest that PcSDA1 plays a similar role in the regulation of the actin cytoskeleton and nuclear division in this filamentous organism as in non-filamentous yeasts and human cells.
authors.affiliation: Department of Plant Pathology, Shandong Agricultural University, 61, Daizong Street, Tai'an, Shandong, 271018, China.
authors.forename: Chunyuan
authors.initials: C
authors.lastname: Zhu
authors.affiliation: Department of Plant Pathology, Shandong Agricultural University, 61, Daizong Street, Tai'an, Shandong, 271018, China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Plant Pathology, Shandong Agricultural University, 61, Daizong Street, Tai'an, Shandong, 271018, China.
authors.forename: Rongfei
authors.initials: R
authors.lastname: Lv
authors.affiliation: Department of Plant Pathology, Shandong Agricultural University, 61, Daizong Street, Tai'an, Shandong, 271018, China.
authors.forename: Zhuang
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Plant Pathology, Shandong Agricultural University, 61, Daizong Street, Tai'an, Shandong, 271018, China.
authors.forename: Xiaomeng
authors.initials: X
authors.lastname: Ding
authors.affiliation: Center for Genome Research and Biocomputing, Oregon State University, Corvallis, OR, 97331, USA.
authors.forename: Brett M
authors.initials: BM
authors.lastname: Tyler
authors.affiliation: Department of Plant Pathology, Shandong Agricultural University, 61, Daizong Street, Tai'an, Shandong, 271018, China.
authors.forename: Xiuguo
authors.initials: X
authors.lastname: Zhang
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism; D000595:Amino Acid Sequence; D002212:Capsicum / Q000382:microbiology; D002453:Cell Cycle; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D020869:Gene Expression Profiling; D020868:Gene Silencing; D025282:Mycelium / Q000254:growth & development* / Q000648:ultrastructure; D009687:Nuclear Proteins / Q000737:chemistry*; D010838:Phytophthora / Q000254:growth & development / Q000472:pathogenicity* / Q000648:ultrastructure; D010935:Plant Diseases / Q000382:microbiology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry*; D020539:Sequence Analysis, Protein; D017386:Sequence Homology, Amino Acid; D013170:Spores / Q000502:physiology / Q000648:ultrastructure; D014774:Virulence
chemical_list: D018797:Cell Cycle Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger; C409685:SDA1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins
keywords: PcSDA1; Phytophthora capsici; actin cytoskeleton; asexual development; nuclear localization; virulence