The Role of Drosophila Endophilin B in Oskar Regulated Endocytosis
| Autor: | Yi Chen Tsai, 蔡佾辰 |
|---|---|
| Rok vydání: | 2009 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 97 The endophilin is a conserved family of protein and was first identified in search for SH3 domain-containing protein. All endophilins contain N-BAR (Bin-Amphiphysin-Rvs) and SH3 (Src-homology 3) domain and have membrane bending potential. Endohpilin B, also called Bif-1 in mammalian, is known to involve in several processes related to its membrane bending ability. In Drosophila, however, the function of Endophilin B is still unknown. We found that only Endophilin B was expressed during oogenesis. In the middle stage egg, D-Endo B was anchored at the oocyte posterior pole and was colocalized with Oskar, a key regulator of germ cells development. In oskar mutant oocyte, D-Endo B was no more assembled at the posterior of oocyte. When ectopically expressing Oskar at the anterior of the oocyte, the D-Endo B was recruited at the same place. We concluded that Oskar controlled the localization of D-Endo B. The oskar message encode two protein isoforms, long and short Oskar and each type of Oskar could recruit D-Endo B. In addition, recent study suggested that Oskar involved in oocyte endoytosis. Since D-EndoB has no defects on pole plasm function, we further investigated the role of D-EndoB in Oskar mediated endocytosis of yolk uptake. We found that D-Endo B was required for the endocytosis activity of the oocyte. The egg production by the endoB54 mutant females decreased, and the percentage of larva hatched from these eggs was less than that from wild type egg. In addition, the yolk content in egg laid by D-EndoB mutant females was less than that in wild type egg. In sum, these data suggest D-EndoB plays a role in regulating fertility through yolk uptake by endocytosis. To further investigate how the special localization of the D-EndoB is achieved, we will examine the localization of D-EndoB mutant protein which lacks the SH3 domain. Unlike Endophilin A, the SH3 domain of D-EndoB doesn’t interact with dynamin in the yeast two-hybrid assay. Taken together, we had found that D-EndoB is involved in Oskar mediated endocytosis in the Drosophila oocyte. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|