TY - JOUR

T1 - The HvNAC6 transcription factor

T2 - a positive regulator of penetration resistance in barley and Arabidopsis

AU - Jensen, Michael Krogh

AU - Rung, Jesper Henrik

AU - Gregersen, Per Langkjær

AU - Gjetting, Torben

AU - Fuglsang, Anja Thoe

AU - Hansen, Michael

AU - Jøhnk, Nina

AU - Lyngkjær, Michael Foged

AU - Collinge, David B.

N1 - Paper id:: 524 kilobytes

PY - 2007

Y1 - 2007

N2 - Pathogens induce the expression of many genes encoding plant transcription factors, though specific knowledge of the biological function of individual transcription factors remains scarce. NAC transcription factors are encoded in plants by a gene family with proposed functions in both abiotic and biotic stress adaptation, as well as in developmental processes. In this paper, we provide convincing evidence that a barley NAC transcription factor has a direct role in regulating basal defence. The gene transcript was isolated by differential display from barley leaves infected with the biotrophic powdery mildew fungus, Blumeria graminis f.sp. hordei (Bgh). The full-length cDNA clone was obtained using 5'-RACE and termed HvNAC6, due to its high similarity to the rice homologue, OsNAC6. Gene silencing of HvNAC6 during Bgh inoculation compromises penetration resistance in barley epidermal cells towards virulent Bgh. Complementing the effect of HvNAC6 gene silencing, transient overexpression of HvNAC6 increases the occurrence of penetration resistant cells towards Bgh attack. Quantitative RT-PCR shows the early and transient induction of HvNAC6 in barley epidermis upon Bgh infection. Additionally, our results show that the Arabidopsis HvNAC6 homologue ATAF1 is also induced by Bgh and the ataf1-1 mutant line shows decreased penetration resistance to this non-host pathogen. Collectively, these data suggest a conserved role of HvNAC6 and ATAF1 in the regulation of penetration resistance in monocots and dicots, respectively.

AB - Pathogens induce the expression of many genes encoding plant transcription factors, though specific knowledge of the biological function of individual transcription factors remains scarce. NAC transcription factors are encoded in plants by a gene family with proposed functions in both abiotic and biotic stress adaptation, as well as in developmental processes. In this paper, we provide convincing evidence that a barley NAC transcription factor has a direct role in regulating basal defence. The gene transcript was isolated by differential display from barley leaves infected with the biotrophic powdery mildew fungus, Blumeria graminis f.sp. hordei (Bgh). The full-length cDNA clone was obtained using 5'-RACE and termed HvNAC6, due to its high similarity to the rice homologue, OsNAC6. Gene silencing of HvNAC6 during Bgh inoculation compromises penetration resistance in barley epidermal cells towards virulent Bgh. Complementing the effect of HvNAC6 gene silencing, transient overexpression of HvNAC6 increases the occurrence of penetration resistant cells towards Bgh attack. Quantitative RT-PCR shows the early and transient induction of HvNAC6 in barley epidermis upon Bgh infection. Additionally, our results show that the Arabidopsis HvNAC6 homologue ATAF1 is also induced by Bgh and the ataf1-1 mutant line shows decreased penetration resistance to this non-host pathogen. Collectively, these data suggest a conserved role of HvNAC6 and ATAF1 in the regulation of penetration resistance in monocots and dicots, respectively.

KW - Former LIFE faculty

KW - ATAF1

KW - Blumeria graminis f.sp. hordei (Bgh)

KW - Expression profiles

KW - HvNAC6

KW - NAC transcription factor

KW - Penetration resistance

U2 - 10.1007/s11103-007-9204-5

DO - 10.1007/s11103-007-9204-5

M3 - Journal article

C2 - 17619150

VL - 65

SP - 137

EP - 150

JO - Plant Molecular Biology

JF - Plant Molecular Biology

SN - 0167-4412

IS - 1-2

ER -