TY - JOUR

T1 - Improved leaf and flower longevity by expressing the etr1-1 allele in Pelargonium zonale under control of FBP1 and SAG12 promoters

AU - Gehl, Christian

AU - Wamhoff, David

AU - Schaarschmidt, Frank

AU - Serek, Margrethe

N1 - Funding information: The authors would like to thank the technical and scientific staff of the Section Floriculture for fruitful discussions and technical assistance, Hermann Schmidt (DNA Cloning Service , Hamburg, Germany) for kindly providing the binary vector set, and Dr. Lynn Hoffman (Stellenbosch University, South Africa) for linguistic editing of the manuscript. The authors declare that they have no conflicts of interest.

PY - 2018/8/28

Y1 - 2018/8/28

N2 - The ethylene receptor etr1-1 (ETHYLENE RESPONSE 1) mutant gene from Arabidopsis thaliana, with its expression under the control of either the Petunia floral binding protein FBP1 promoter or the Arabidopsis senescence-specific SAG12 gene promoter, was introduced into Pelargonium zonale cv. ‘Katinka’. The heterologous expression of these transgenes and the response of flowers and leaves to exogenous ethylene were then studied. Transgenic etr1-1 lines grown in the greenhouse did not differ morphologically or physiologically from nontransformed plants nor was the rooting ability of cuttings affected. Reverse transcription (RT)-PCR revealed that transcripts from an FBP1 promoter were present from green tissue to the roots, whereas the SAG12 promoter was only active in processes associated with aging or senescence of flower petals and leaves. The sensitivity to ethylene exposure was markedly reduced by using both promoter constructs. Flower petals from nontransformed controls were fully senescent 4 days after ethylene exposure, while more than 90% of the flower petals from FBP1-promoter lines and over 50% of the flower petals from SAG12-promoter lines remained unchanged, without showing any signs of wilting or any response to ethylene. However, ethylene sensitivity of leaves was only delayed in the best lines but not suppressed through etr1-1 expression. Foliage displayed less intense leaf yellowing and wilting, which were similar for both promoter variants compared to wild type controls.

AB - The ethylene receptor etr1-1 (ETHYLENE RESPONSE 1) mutant gene from Arabidopsis thaliana, with its expression under the control of either the Petunia floral binding protein FBP1 promoter or the Arabidopsis senescence-specific SAG12 gene promoter, was introduced into Pelargonium zonale cv. ‘Katinka’. The heterologous expression of these transgenes and the response of flowers and leaves to exogenous ethylene were then studied. Transgenic etr1-1 lines grown in the greenhouse did not differ morphologically or physiologically from nontransformed plants nor was the rooting ability of cuttings affected. Reverse transcription (RT)-PCR revealed that transcripts from an FBP1 promoter were present from green tissue to the roots, whereas the SAG12 promoter was only active in processes associated with aging or senescence of flower petals and leaves. The sensitivity to ethylene exposure was markedly reduced by using both promoter constructs. Flower petals from nontransformed controls were fully senescent 4 days after ethylene exposure, while more than 90% of the flower petals from FBP1-promoter lines and over 50% of the flower petals from SAG12-promoter lines remained unchanged, without showing any signs of wilting or any response to ethylene. However, ethylene sensitivity of leaves was only delayed in the best lines but not suppressed through etr1-1 expression. Foliage displayed less intense leaf yellowing and wilting, which were similar for both promoter variants compared to wild type controls.

KW - Ethylene receptor

KW - Etr1-1 mutant gene

KW - FBP1-promoter

KW - Flower longevity

KW - Leaf yellowing

KW - SAG12-promoter

UR - http://www.scopus.com/inward/record.url?scp=85053182356&partnerID=8YFLogxK

U2 - 10.1007/s10725-018-0434-0

DO - 10.1007/s10725-018-0434-0

M3 - Article

AN - SCOPUS:85053182356

VL - 86

SP - 351

EP - 363

JO - Plant growth regulation

JF - Plant growth regulation

SN - 0167-6903

IS - 3

ER -