TY - JOUR
T1 - Conservation in Function of a SCAR/WAVE Component during Infection Thread and Root Hair Growth in Medicago truncatula
AU - Miyahara, Akira
AU - Richens, Jennifer
AU - Starker, Colby
AU - Morieri, Giulia
AU - Smith, Lucinda
AU - Long, Sharon
AU - Downie, J. Allan
AU - Oldroyd, Giles E.D.
PY - 2010/12
Y1 - 2010/12
N2 - Nitrogen-fixing symbioses of plants are often associated with bacterially infected nodules where nitrogen fixation occurs. The plant host facilitates bacterial infection with the formation of infection threads, unique structures associated with these symbioses, which are invaginations of the host cell with the capability of traversing cellular junctions. Here, we show that the infection thread shares mechanistic similarities to polar-growing cells, because the required for infection thread (RIT) locus of Medicago truncatula has roles in roothair, trichome, and infection-thread growth. We show that RIT encodes the M. truncatula ortholog of NAP1, a component of the SCAR/WAVE (suppressor of cAMP receptor/ WASP-family verprolin homologous protein) complex that regulates actin polymerization, through the activation of ARP2/3. NAP1 of Arabidopsis thaliana functions equivalently to the M. truncatula gene, indicating that the mode of action of NAP1 is functionally conserved across species and that legumes have not evolved a unique functionality for NAP1 during rhizobial colonization. This work highlights the surprising commonality between polar-growing cells and a polar-growing cellular intrusion and reveals important insights into the formation and maintenance of infectionthread development.
AB - Nitrogen-fixing symbioses of plants are often associated with bacterially infected nodules where nitrogen fixation occurs. The plant host facilitates bacterial infection with the formation of infection threads, unique structures associated with these symbioses, which are invaginations of the host cell with the capability of traversing cellular junctions. Here, we show that the infection thread shares mechanistic similarities to polar-growing cells, because the required for infection thread (RIT) locus of Medicago truncatula has roles in roothair, trichome, and infection-thread growth. We show that RIT encodes the M. truncatula ortholog of NAP1, a component of the SCAR/WAVE (suppressor of cAMP receptor/ WASP-family verprolin homologous protein) complex that regulates actin polymerization, through the activation of ARP2/3. NAP1 of Arabidopsis thaliana functions equivalently to the M. truncatula gene, indicating that the mode of action of NAP1 is functionally conserved across species and that legumes have not evolved a unique functionality for NAP1 during rhizobial colonization. This work highlights the surprising commonality between polar-growing cells and a polar-growing cellular intrusion and reveals important insights into the formation and maintenance of infectionthread development.
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U2 - 10.1094/MPMI-06-10-0144
DO - 10.1094/MPMI-06-10-0144
M3 - Article
C2 - 20731530
AN - SCOPUS:78649484621
SN - 0894-0282
VL - 23
SP - 1553
EP - 1562
JO - Molecular Plant-Microbe Interactions
JF - Molecular Plant-Microbe Interactions
IS - 12
ER -