Arabidopsis formin AtFH6 is a plasma membrane-associated protein upregulated in giant cells induced by parasitic nematodes.
Plant-parasitic nematodes Meloidogyne spp induce an elaborate permanent feeding site characterized by the redifferentiation of root cells into multinucleate and hypertrophied giant cells. We have isolated by a promoter trap strategy an Arabidopsis thaliana formin gene, AtFH6, which is upregulated during giant cell formation. Formins are actin-nucleating proteins that stimulate de novo polymerization of actin filaments. We show here that three type-I formins were upregulated in giant cells and that the AtFH6 protein was anchored to the plasma membrane and uniformly distributed. Suppression of the budding defect of the Saccharomyces cerevisiae bni1Delta bnr1Delta mutant showed that AtFH6 regulates polarized growth by controlling the assembly of actin cables. Our results suggest that AtFH6 might be involved in the isotropic growth of hypertrophied feeding cells via the reorganization of the actin cytoskeleton. The actin cables would serve as tracks for vesicle trafficking needed for extensive plasma membrane and cell wall biogenesis. Therefore, determining how plant parasitic nematodes modify root cells into giant cells represents an attractive system to identify genes that regulate cell growth and morphogenesis.
Institut National de la Recherche Agronomique, Unité Mixte de Recherche Interactions Plantes-Microorganismes et Santé Végétale, 06903 Sophia-Antipolis BP167, France.
Bruno
B
Favery
Liudmila A
LA
Chelysheva
Manuel
M
Lebris
Fabien
F
Jammes
Anne
A
Marmagne
Janice
J
De Almeida-Engler
Philippe
P
Lecomte
Chantal
C
Vaury
Robert A
RA
Arkowitz
Pierre
P
Abad
D000199:Actins / Q000378:metabolism; D000595:Amino Acid Sequence / Q000235:genetics; D000818:Animals; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism* / Q000469:parasitology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001483:Base Sequence / Q000235:genetics; D002462:Cell Membrane / Q000235:genetics / Q000378:metabolism; D002473:Cell Wall / Q000235:genetics / Q000378:metabolism; D018076:DNA, Complementary / Q000032:analysis / Q000235:genetics; D000080865:Formins; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D005966:Glucuronidase / Q000378:metabolism; D006790:Host-Parasite Interactions / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008840:Microfilament Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009349:Nematode Infections / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D022161:Transport Vesicles / Q000235:genetics / Q000378:metabolism; D014431:Tylenchoidea / Q000378:metabolism*; D015854:Up-Regulation / Q000235:genetics
D000199:Actins; D029681:Arabidopsis Proteins; D018076:DNA, Complementary; C493662:FH6 protein, Arabidopsis; D000080865:Formins; D008565:Membrane Proteins; D008840:Microfilament Proteins; D005966:Glucuronidase