Cellulose synthesis in Phytophthora infestans is required for normal appressorium formation and successful infection of potato.
Cellulose, the important structural compound of cell walls, provides strength and rigidity to cells of numerous organisms. Here, we functionally characterize four cellulose synthase genes (CesA) in the oomycete plant pathogen Phytophthora infestans, the causal agent of potato (Solanum tuberosum) late blight. Three members of this new protein family contain Pleckstrin homology domains and form a distinct phylogenetic group most closely related to the cellulose synthases of cyanobacteria. Expression of all four genes is coordinately upregulated during pre- and early infection stages of potato. Inhibition of cellulose synthesis by 2,6-dichlorobenzonitrile leads to a dramatic reduction in the number of normal germ tubes with appressoria, severe disruption of the cell wall in the preinfection structures, and a complete loss of pathogenicity. Silencing of the entire gene family in P. infestans with RNA interference leads to a similar disruption of the cell wall surrounding appressoria and an inability to form typical functional appressoria. In addition, the cellulose content of the cell walls of the silenced lines is >50% lower than in the walls of the nonsilenced lines. Our data demonstrate that the isolated genes are involved in cellulose biosynthesis and that cellulose synthesis is essential for infection by P. infestans.
Grenville-Briggs
Laura J
LJ
Aberdeen Oomycete Group, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen, AB25 2ZD, United Kingdom.
Anderson
Victoria L
VL
Fugelstad
Johanna
J
Avrova
Anna O
AO
Bouzenzana
Jamel
J
Williams
Alison
A
Wawra
Stephan
S
Whisson
Stephen C
SC
Birch
Paul R J
PR
Bulone
Vincent
V
van West
Pieter
P
D020418:Algal Proteins / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D002473:Cell Wall / Q000378:metabolism*; D002482:Cellulose / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D005964:Glucosyltransferases / Q000145:classification / Q000235:genetics / Q000378:metabolism; D046529:Microscopy, Electron, Transmission; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010802:Phylogeny; D010838:Phytophthora / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D010935:Plant Diseases / Q000382:microbiology; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D011198:Solanum tuberosum / Q000382:microbiology*
D020418:Algal Proteins; D002482:Cellulose; D005964:Glucosyltransferases; C478648:cellulose synthase