Progress 09/01/05 to 08/31/10
Outputs
OUTPUTS: The long term goal of this project is to modulate sexual reproduction in crops to enhance productivity. The immediate goal is to dissect the interaction between the male-gamete-containing pollen and the pollen-receiving female in the flower. We have found that maize (corn) pollen coat contains several active hydrolytic enzymes. We have explored the mode of synthesis of these enzymes in the cells of the tapetum layer enclosing the maturing pollen and their function on the pollen-receiving structure (stigma) of the female during sexual reproduction. Three hydrolytic enzymes, xylanase, glucanase, and protease have been localized in different subcellular compartments, and they are discharged to the pollen surface via different mechanisms. Via an anti-sense approach, we have documented that the pollen coat xylanase facilitates pollen tube penetration into silk during sexual reproduction. In an expansion of our corn work, we have found that in Brassica (cabbage family that includes many vegetables and canola oil crop), the tapetum contains storage tapetosomes that accumulate endoplasmic reticulum-derived flavonoids and alkanes for delivery to the pollen surface. We have obtained several transcriptomes of rice anthers with the latest SBS technology and are analyzing the transcriptomes for (1) secretory proteins synthesized in the tapetum, (2) tapetum proteins involved in the formation of the pollen surface exine, and (3) appropriate gene promoters for the future making of seedless fruits and hybrid seeds. PARTICIPANTS: Not relevant to this project. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Not relevant to this project.
Impacts
Results of the current study will guide us to modulate sexual reproduction in crops to enhance productivity. Promoting sexual reproduction could enhance the yield of fruits and seeds. Suppressing the process could increase the production of leafy vegetables. Also, male sterility technology can be used to produce hybrid seeds, generate seedless fruits, and silence pollen from genetically-modified crops.
Publications
- Suen D, Huang AHC. 2007. Maize pollen coat xylanase facilitates pollen tube penetration into silk during sexual reproduction. J. Biol. Chem. 282: 625-636. (featured on issue cover; 282:[1])
- Hsieh K, Huang AHC. 2007. Tapetosomes in Brassica tapetum accumulate endoplasmic reticulum-derived flavonoids and alkanes for delivery to the pollen surface. Plant Cell 19:582-596.
- Hsieh K, Huang AHC. USDA-NRI Cover story. 2007: Number 5.
- Suen D, Huang AHC. USDA-NRI Cover story. 2007: Number 11.
- Huang MD, Wei FJ, Wu CC, Hsing YIC, Huang AHC. 2009. Analyses of advanced rice anther transcriptomes reveal global tapetum secretory functions and potential proteins for lipid exine formation. Plant Physiol. 149: 694-707.
- Huang CY, Chung CI, Lin YC, Hsing YIC, Huang AHC. 2009. Oil bodies and oleosins in Physcomitrella possess characteristics representative of early trends in evolution. Plant Physiol. 150: 1192-1203. (featured on issue cover; 150:[3])
|
Progress 09/01/08 to 08/31/09
Outputs
OUTPUTS: The long term goal of this project is to modulate sexual reproduction in crops to enhance productivity. The immediate goal is to dissect the interaction between the male-gamete-containing pollen and the pollen-receiving female in the flower. Maize pollen coat contains 3 hydrolytic enzymes, xylanase, glucanase and protease, which were synthesized in the adjacent tapetum cells. We have characterized these enzymes in terms of their sub-tissue and sub-cellular locations in the tapetum and the modes of their discharge from the tapetum to the locule and then the microspore surface. We have shown, with use of an anti-sense approach, that the pollen coat xylanase facilitates pollen tube penetration into silk during sexual reproduction. We have obtained 7 high-quality SBS transcriptomes of rice anthers and mature pollen. Analyses of these transcriptomes reveal global tapetum secretory functions and potential proteins for lipid exine formation. We are characterizing these exine-forming proteins. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Results of the current study will guide us to modulate sexual reproduction in crops to enhance productivity. Promoting sexual reproduction could enhance the yield of fruits and seeds. Suppressing the process could increase the production of leafy vegetables. Also, male sterility technology can be used to produce hybrid seeds, generate seedless fruits, and silence pollen from genetically-modified crops.
Publications
- Huang MD, Wei FJ, Wu CC, Hsing YIC, Huang AHC. 2009. Analyses of advanced rice anther transcriptomes reveal global tapetum secretory functions and potential proteins for lipid exine formation. Plant Physiol. 149: 694-707.
|
Progress 09/01/07 to 08/31/08
Outputs
OUTPUTS: The long term goal of this project is to modulate sexual reproduction in crops to enhance productivity. The immediate goal is to dissect the interaction between the male-gamete-containing pollen and the pollen-receiving female in the flower. We have found that maize (corn) pollen coat contains several active hydrolytic enzymes. We have explored the mode of synthesis of these enzymes in the cells of the tapetum layer enclosing the maturing pollen and their function on the pollen-receiving structure (stigma) of the female during sexual reproduction. Three hydrolytic enzymes, xylanase, glucanase, and protease have been localized in different subcellular compartments, and they are discharged to the pollen surface via different mechanisms. Via an anti-sense approach, we have documented that the pollen coat xylanase facilitates pollen tube penetration into silk during sexual reproduction. In an expansion of our corn work, we have found that in Brassica (cabbage family that includes many vegetables and canola oil crop), the tapetum contains storage tapetosomes that accumulate endoplasmic reticulum-derived flavonoids and alkanes for delivery to the pollen surface. We have obtained several transcriptomes of rice anthers with the latest SBS technology and are analyzing the transcriptomes for (1) secretory proteins synthesized in the tapetum, (2) tapetum proteins involved in the formation of the pollen surface exine, and (3) appropriate gene promoters for the future making of seedless fruits and hybrid seeds. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Not relevant to this project.
Impacts
Results of the current study will guide us to modulate sexual reproduction in crops to enhance productivity. Promoting sexual reproduction could enhance the yield of fruits and seeds. Suppressing the process could increase the production of leafy vegetables. Also, male sterility technology can be used to produce hybrid seeds, generate seedless fruits, and silence pollen from genetically-modified crops.
Publications
- No publications reported this period
|
Progress 09/01/06 to 08/31/07
Outputs
The long term goal of this project is to modulate sexual reproduction in crops to enhance productivity. The immediate goal is to dissect the interaction between the male-gamete-containing pollen and the pollen-receiving female in the flower. We have found that maize (corn) pollen coat contains several active hydrolytic enzymes. We have explored the mode of synthesis of these enzymes in the cells of the tapetum layer enclosing the maturing pollen and their function on the pollen-receiving structure (stigma) of the female during sexual reproduction. Three hydrolytic enzymes, xylanase, glucanase, and protease have been localized in different subcellular compartments, and they are discharged to the pollen surface via different mechanisms. Via an anti-sense approach, we have documented that the pollen coat xylanase facilitates pollen tube penetration into silk during sexual reproduction. In an expansion of our corn work, we have found that in Brassica (cabbage family that
includes many vegetables and canola oil crop), the tapetum contains storage tapetosomes that accumulate endoplasmic reticulum-derived flavonoids and alkanes for delivery to the pollen surface.
Impacts
Results of the current study will guide us to modulate sexual reproduction in crops is important to productivity. Promoting sexual reproduction could enhance the yield of fruits and seeds. Suppressing the process could increase the production of leafy vegetables. Also, male sterility technology can be used to produce hybrid seeds, generate seedless fruits, and silence pollen from genetically-modified crops.
Publications
- Suen D, Huang AHC. 2007. Maize pollen coat xylanase facilitates pollen tube penetration into silk during sexual reproduction. J. Biol. Chem. 282: 625-636.
- Hsieh K, Huang AHC. 2007. Tapetosomes in Brassica tapetum accumulate endoplasmic reticulum-derived flavonoids and alkanes for delivery to the pollen surface. Plant Cell 19:582-596.
|
Progress 09/01/05 to 08/31/06
Outputs
The long term goal of this project is to modulate sexual reproduction in crops to enhance productivity. The immediate goal is to dissect the interaction between the male-gamete-containing pollen and the pollen-receiving female in the flower. We have found that maize (corn) pollen coat contains several active hydrolytic enzymes. We have explored the mode of synthesis of these enzymes in the cells of the tapetum layer enclosing the maturing pollen and their function on the pollen-receiving structure (stigma) of the female during sexual reproduction. Three hydrolytic enzymes, xylanase, glucanase, and protease have been localized in different subcellular compartments, and they are discharged to the pollen surface via different mechanisms. We are using biochemical fractionation and microscopy to dissect these mechanisms. The function of the pollen-coat xylanase in creating an opening on the stigma enzymatically for pollen tube entry is being explored with xylanase-less
pollen generated via antisense transformation. We are exploring using rice in addition to maize genomic databases to examine the global secretory function of the tapetum.
Impacts
Results of the current study will guide us to modulate sexual reproduction in crops is important to productivity. Promoting sexual reproduction could enhance the yield of fruits and seeds. Suppressing the process could increase the production of leafy vegetables. Also, male sterility technology can be used to produce hybrid seeds, generate seedless fruits, and silence pollen from genetically-modified crops. Results of the current stud
Publications
- No publications reported this period
|
|