by Sophie Fessl, Gregor Mendel Institut für Molekulare Pflanzenbiologie (GMI)
Viruses are a threat to all organisms, including plants. A small group of plant stem cells, however, successfully defends itself from infection.
Marco Incarbone, now at MPIMP Golm, Gabriele Bradamante and their co-authors at the Gregor Mendel Institute of Molecular Plant Biology (GMI) uncovered that salicylic acid and RNA interference mediate this antiviral immunity of plant stem cells. The findings were published in PNAS on October 12.
Plant viruses threaten the health of their hosts, can spread swiftly and globally, and challenge agricultural productivity. When viruses successfully infect plants, the infection often spreads through the entire organism. Well, not entirely: One small group of indomitable cells still holds out, the stem cells within the shoot tip. This small group of cells generates all plant tissues above ground, including the next plant generation, and for reasons still poorly understood, viruses are unable to proliferate in these cells.