| Project/Area Number |
09680674
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Molecular biology
|
|---|
| Research Institution | Health Research Foundation (1998)
Kyoto University (1997) |
|---|
Principal Investigator |
YAMAGISHI Hideo Health Research Foundation Principal Scientist, 主任研究員 (90025429)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
EKINO Shigeo Kumamoto Univ., Fac.Medicine Professor, 医学部, 教授 (30125273)
SHIMIZU Akira Kyoto Univ., Center for Mol.Biol. Professor, 遺伝子実験施設, 教授 (00162694)
UDAKA Keiko Kyoto Univ., Fac.Science, Research Associate, 大学院・理学研究科, 助手 (40263066)
|
|---|
| Project Period (FY) |
1997 – 1998
|
| Project Status |
Completed (Fiscal Year 1998)
|
| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 1998: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1997: ¥2,900,000 (Direct Cost: ¥2,900,000)
|
|---|
| Keywords | Bursa Fabricius / Germinal center / Immunoglobulin / PCR method / Affinity maturation / Gene conversion / Point mutation / Class switch recombination / 抗体遺伝子 / NPハプテン / 抗原親和性 / クラススイツチ組換え / FITCハプテン / 高親和性 / 体細胞突然変異 / クラススイッチ領域 |
|---|
| Research Abstract |
Chicken bursal follicles and germinal centers enabled us to analyze the bursal and postbursal diversification of B-cells due to its easy isolation and the PCR amplification of immunoglobulin genes.Antigen-independent bursal B-cell diversification by gene conversions and point mutations generated crippling mutations at the high yield of 50% before hatching but the crippling mutation ratio was dramatically decreased by antigen-dependent positive selection after hatching.Postbursal B-cells migrating into single germinal centers are further diversified by gene conversion in the early phase of germinal center reaction and are subsequently subjected to point mutations and selection for oligoclonality which may represent an intermediate step of affinity maturation.We characterized two switch regions, Smu region of 5 kb long composed of TATGG and ACCAQ pentameric repeats and S gamma region of TATGG and GGCAG repeats and showed deletional switch recombinations between these two regions.
|
