2006 Fiscal Year Final Research Report Summary
Establishment of hybrid transgenic edible rice plant vaccines with metabolism-enhanced transgenic rice plants for the increased antigen production.
| Project/Area Number |
16380198
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Basic veterinary science/Basic zootechnical science
|
|---|
| Research Institution | The University of Tokyo |
|---|
Principal Investigator |
YASUNOBU Matsumoto The University of Tokyo, Graduate School of Agricultural and Life Sciences, Associate Professor (90251420)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
HAYASHI Yoshihiro The University of Tokyo, Graduate School of Agricultural and Life Sciences, Professor (90092303)
|
|---|
| Project Period (FY) |
2004 – 2006
|
| Keywords | edible vaccine / Transgenic plants / oral administration of rice seeds / Ascaris suum / mucosal immunity / protective antigen / hybrid / transgenic rice with C4 genes |
|---|
| Research Abstract |
Edible vaccine is a safe, cheap and painless alternative method for vaccine delivery system. We have generated a transgenic rice plants producing an Ascaris suum 3^<rd> stage larvae protective antigen, As16, in their seeds by introducing the cDNA under the control of Gluterin B promoter. The transgenic seeds produced As16 and mice administered those seeds with cholera toxin (CT) adjuvant showed reduced infectivity to orally infected A.suum. However, the necessity of CT adjuvant suggested the importance of the increase in the As16 protein amount in each seeds. Thus, we have planned to perform cross mating the As16-producing our transgenic rice plants, designated as tgRICE/CTBAs16, with a metabolism-enhanced rice plants by introducing genes for photosynthesis derived from C4 plants such as corn, generated by Dr.Ku in Washington State University (WSU). A couple of accidents had occurred during the project. Firstly, although 2^<nd> generation of tgRICE/CTBAs16 maintained the As16 productio
… More
n levels similar to those of 1^<st> generation plants. However, the 3^<rd> generation of them showed only 10% of As16 protein production levels compared to 1^<st> and 2^<nd> generations (2004). Secondly, Dr.Ku left WSU and we could not continue our collaboration (2005). From these reasons, we decided to modify our research direction from the establishment and analysis of cross bled transgenic rice between tgRICE/CTBAs16 and C4 gene-introduced rice plants to the research for enhancing the As16 production level by other ways. By optimizing As16 codons from native A.suum type to rice seed type, As16 protein production level was increased to double of the original codon in wheat germ cell free protein expression system (2005). In 2006, tgRICE/CTBAs16 was cross bled with wild type and another transgenic rice plants since recovery of exogenous protein production levels was often observed by mix-bleeding of some transgenic plants. However, the As16 production levels of homogeneous tgRICE/CTBAs16 seeds and those of F1 plants were not different, suggesting the decrease in the As16 production levels were not related to silencing mechanism which can be terminated by activating gene with cross-bleeding. By considering these results, further trials to increase the As16 production levels should be done. Less
|
