| Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 2006: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2005: ¥1,200,000 (Direct Cost: ¥1,200,000)
|
|---|
| Research Abstract |
mRNA localization within cells and translational regulation that couples to the mRNA localization is an essential for the establishing of cell polarity. Drosophila oocyte is the ideal model for studying the mechanism of the mRNA localization and the translational control. Recent studies have revealed that splicing of RNA in the nucleus is important for the cytosolic mRNA localization. We have identified a Drosophila nuclear-cytoplasm shuttling protein, Hrp48, that is essential for the localization of oskar mRNA to the poaterior of the oocyte, and for the translational repression of oskar RNA. Hrp48 is a homologue of mammalian A/B type hnRNP, and is shown to'be essential for the inhibition of the splicing of p-element RNA. The purpose of this research is to clarify how splicing in nucleus affects the cytoplasmic mRNA localization and translational regulation by analyzing Hrp48 containing protein complex.
We have analyzed these below :
1. Domain analysis of Hrp48 in vivo
2. Nuculear localization signal in Hrp48
3. Identification of factor(s) that makes a complex with Hrp48 in the nucleus
By the analysis 1, we showed that glycin rich domainin of Hrp48 (which has no RNA binding domain) is important for the complex formation that is essential for the translational repression of oskar mRNNA. In addition, we suggested that this domain interacts with factor(s) that is critical for the cytoplasmic localization of gurken mRNA in anterior-dorsal part of the ocyte.
By the analysis 2, we identified the nuclear localization signal in Hrp48, which is partly homologous to M9 sequence that act as a nuclear localization signal in hnRNP Al in mammals.
By the analysis 3, we identified factors that make a complex with Hrp48 in the nucleus. These factors cannot make a complex with mutated Hrp48 that is impossible to go into the nucleus.
|
