Drosophila decapping protein 2, dDcp2,regulates microtubule organization in the oocyte
Date Issued
2009
Date
2009
Author(s)
Lai, Ying-Chu
Abstract
Microtubules and actin filaments are required for the selective accumulation of oskar(osk) mRNA at the posterior end in the Drosophila oocyte. Our previous research uncovered that Drosophila decapping protein 2, dDcp2, is necessary for the proper posterior location of osk mRNP complex. The posterior determinants— Osk, Staufen and Vasa display a mislocalized pattern in dDcp2 deletion mutant comparing with the posterior crescent pattern in wild type oocyte. More strikingly, an abnormal actin accumulation clumps and a halted ooplasmic streaming were found in the mid and late stage of the dDcp2 mutant oocytes. ince microtubules dominants the localization of maternal determinants and the onset of ooplasmic streaming, we suspect that dDcp2 may modulate the intracellular microtubule network during oogenesis. This working hypothesis is supported by several observations. irst, dDcp2 mutants show a disorganization of the oocyte microtubule cytoskeleton. Comparing with wild type, dDcp2 mutants is defected in the dynamic reorientation of microtubule at stage 9. Moreover, microtubule bundles can’t form a typical parallel array during stage 10B in dDcp2de21, dDcp2RAf, and dDcp2NF mutant GLC oocytes. Microtubules are less abundant in dDcp2 mutants, showing that a key function of dDcp2 in vivo is maintenance of the microtubule cytoskeleton.econd, α-tubulin protein expression level is reduced in dDcp2 and dGe-1/dHedls mutant larvae, respectively; similarly, the dynamic tyrosinated tubulin protein expression level is also decreased in the dDcp2 de21 mutant GLC oocytes, and this might explain the effect on the microtubule cytoskeleton.hird, dDcp2 is required for successful completion for the early embryo development in Drosophila. The loss-of-function of dDcp2 results in defects in the proper alignment of the dynamic spindles and chromosomal motions in early embryos.inally, dDcp1 and dDcp2 are partially colocalized in Drosophila S2 cells. We further showed that components of processing bodies such as dDcp1, dDcp2 and dGe-1/dHedls are able to adhere to microtubule filaments.everal findings suggest that a relationship exists between Processing bodies and microtubules. The disruption of microtubule by drug can stimulate the accumulation of P-bodies in yeast and mammalian cells, whereas the 5’-3’ exonuclease Xrn1 is able to promote the assembly of tubulin into microtubule in vitro. Further, the loss-of-function of GW182 protein can lead to the aggregation of tubulin filamentous in Drosophila embryos.ur findings indicate that dDcp2, as a component of P-bodies, may have a specific function in remodeling microtubule organization which appears unrelated toits RNA decapping function in vegetative cells. Therefore, we suspect that in dDcp2 mutation the disruption of microtubule may in turn affect the organization of actin filament and the proper chromosome segregation during mitosis.
Subjects
decapping protein
microtubule
File(s)![Thumbnail Image]()
Loading...
Name
ntu-98-R96b43008-1.pdf
Size
23.32 KB
Format
Adobe PDF
Checksum
(MD5):8c46e4cc8a1ae97b85be959ba649bd9a