1998 Fiscal Year Final Research Report Summary
Cellular and Molecular Breeding of Sesame.
| Project/Area Number |
09660003
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Breeding science
|
|---|
| Research Institution | Toyama University |
|---|
Principal Investigator |
YAMADA Kyoji Fac.of Sci., Toyama Univ., Professor, 理学部, 教授 (70200714)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
WAKASUGI Tatsuya Fac.of Sci., Toyama Univ., Associate Professor, 理学部, 助教授 (10212317)
|
|---|
| Project Period (FY) |
1997 – 1998
|
| Keywords | Sesame / Oilseed crop / Molecular breeding / Unsaturated fatty acid / Fatty acid desaturase / transgenic plant / Agrobacterium / 形質転換 |
|---|
| Research Abstract |
(i) We isolated full-length cDNA clones coding for two fatty acid desaturases from sesame, Sesamum indicum : a microsomal omega-6 desaturase which is required for conversion of oleic to linoleic acids and a plastid-localiz- ed omega-3 desaturase which is required for conversion of linoleic to linolenic acids. Sequence analysis indicated that the former cDNA clone included an open reading frame (ORF) of 383 amino acids, while the latter clone that of 447 amino acids. We also cloned a cDNA which encodes about one-third of a plasatid-localized omega-6 fatty acid desaturase.
(ii) Northern blot analyses showed changes in the transcription level of the above three fatty acid desaturases at various developmental stages and among different organs in sesame. A gene for an microsomal omega-6 desaturase was found to be transcribed at high level specifically in seeds at their immature stages, whereas the transcripts of plastid-localized type of both omega-6 and omega-3 desaturases were almost undetectable in various organs at all developmental stages.
(iii) We have succeeded in cloning a genomic DNA of an microsomal omega-6 fatty acid desaturase of sesame, determined its nucleotide sequences, and then found that a 1.6 kbp intron was located at only 25 bp before the initiation codon of the coding region. At least 14 cis-regulatory elements, such as E-box, which are specific sequence motifs known to be effective for high expression of specific genes during seed development, were detected within the intron.
(iv) We tried to transform sesame plants by infection of Agrobacterium. when infected with A.tumefaciens containing the MAT vector (pMAT21), seedlings of a wild species, Sesamum schinzianum frequently produced crown galls. Incubation of the calli derived from the goals resulted in regenera- tion of plantlets at high frequency. Confirmation of transformation in such regenerated plants is now in progress.
|
