TY - JOUR
T1 - Effect of pollination on accumulation of ACC synthase and ACC oxidase transcripts, ethylene production and flower petal abscission in geranium (Pelargonium x hortorum L.H. Bailey)
AU - Clark, David G.
AU - Richards, Christina
AU - Hilioti, Zoe
AU - Lind-Iversen, Solveig
AU - Brown, Kathleen
N1 - Funding Information:
This work was supported, in part, by research grants from the Fred C. Gloeckner Foundation, the American Floral Endowment, and grants to Z.H. from the Ger-ondelis Foundation and the State Scholarship Foundation of Greece. The authors thank Trina Shubert for assisting with microscopic examination of pollen tube growth.
PY - 1997/8
Y1 - 1997/8
N2 - Self-pollination of diploid zonal geranium (Pelargonium x hortorum L.H. Bailey) florets leads to a dramatic rise in ethylene production, followed by abscission within 4 h. Neither wounding of the stigma, pollination with tetraploid pollen, nor heat-killed self pollen could elicit as much ethylene production and petal abscission as selfpollination. A cDNA sharing sequence identity with ACC synthase (GACS2) and three different cDNAs sharing sequence identity with ACC oxidase (GACO1, GACO2, GACO3) were isolated from geranium pistils. Transcripts hybridizing with these probes increased slightly in response to self-pollination, but the degree of accumulation in response to various treatments did not correlate with ethylene production. When calculated on a per-plant-part basis, transcripts hybridizing with GACS2 were equally distributed among the stigma+style, sterile ovary, and ovary tissues, but transcripts hybridizing with the three ACC oxidase clones were differentially distributed. All transcripts were differentially expressed among the other tissues of the plant, with GACO1 being the most widely distributed. Ethylene production in geranium pistils was not autocatalytic. Propylene failed to induce ethylene production and ethylene did not induce the accumulation of ACC synthase or ACC oxidase transcripts. ACC accumulated in the stigma and style, and to a smaller extent in the sterile ovary, after pollination. These data support a model of pollination-induced ethylene production by post-transcriptional regulation of ethylene biosynthetic gene expression.
AB - Self-pollination of diploid zonal geranium (Pelargonium x hortorum L.H. Bailey) florets leads to a dramatic rise in ethylene production, followed by abscission within 4 h. Neither wounding of the stigma, pollination with tetraploid pollen, nor heat-killed self pollen could elicit as much ethylene production and petal abscission as selfpollination. A cDNA sharing sequence identity with ACC synthase (GACS2) and three different cDNAs sharing sequence identity with ACC oxidase (GACO1, GACO2, GACO3) were isolated from geranium pistils. Transcripts hybridizing with these probes increased slightly in response to self-pollination, but the degree of accumulation in response to various treatments did not correlate with ethylene production. When calculated on a per-plant-part basis, transcripts hybridizing with GACS2 were equally distributed among the stigma+style, sterile ovary, and ovary tissues, but transcripts hybridizing with the three ACC oxidase clones were differentially distributed. All transcripts were differentially expressed among the other tissues of the plant, with GACO1 being the most widely distributed. Ethylene production in geranium pistils was not autocatalytic. Propylene failed to induce ethylene production and ethylene did not induce the accumulation of ACC synthase or ACC oxidase transcripts. ACC accumulated in the stigma and style, and to a smaller extent in the sterile ovary, after pollination. These data support a model of pollination-induced ethylene production by post-transcriptional regulation of ethylene biosynthetic gene expression.
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U2 - 10.1023/A:1005877809905
DO - 10.1023/A:1005877809905
M3 - Article
C2 - 9290638
AN - SCOPUS:0031213572
SN - 0167-4412
VL - 34
SP - 855
EP - 865
JO - Plant molecular biology
JF - Plant molecular biology
IS - 6
ER -