During Drosophila oogenesis, the targeted localization of gurken (grk) mRNA leads to the establishment of the axis polarity of the egg. In early stages of oogenesis, grk mRNA is found at the posterior of the oocyte, whereas in the later stages grk mRNA is positioned at the dorsal anterior corner of the oocyte. In order to visualize the real-time localization and anchorage of endogenous grk mRNA...

The actin nucleation factor Arp2/3 complex is a main regulator of actin assembly and is involved in multiple processes like cell migration and adhesion, endocytosis, and the establishment of cell polarity in mitosis. Our previous work showed that the Arp2/3 complex was involved in the actin-mediated mammalian oocyte asymmetric division. However, the regulatory mechanisms and signaling pathway o...

Previous work has demonstrated a role for the Drosophila EGF receptor (Torpedo/DER) and its ligand, Gurken, in the determination of anterioposterior and dorsoventral axes of the follicle cells and oocyte. The roles of DER in establishing the polarity of the follicle cells were examined further, by following the expression of DER-target genes. One class of genes (e.g. kekon) is induced by the DE...

BACKGROUND Motor proteins of the minus end-directed cytoplasmic dynein and plus end-directed kinesin families provide the principal means for microtubule-based transport in eukaryotic cells. Despite their opposing polarity, these two classes of motors may cooperate in vivo. In Drosophila circumstantial evidence suggests that dynein acts in the localization of determinants and signaling factors ...

A conditional block to transcriptional elongation is an important mechanism for regulating c-myc gene expression. This elongation block within the first c-myc exon was defined originally in mammalian cells by nuclear run-on transcription analyses. Subsequent oocyte injection and in vitro transcription analyses suggested that sequences near the end of the first c-myc exon are sites of attenuatio...

Meiotic checkpoints monitor chromosome status to ensure correct homologous recombination, genomic integrity, and chromosome segregation. In Drosophila, the persistent presence of double-strand DNA breaks (DSB) activates the ATR/Mei-41 checkpoint, delays progression through meiosis, and causes defects in DNA condensation of the oocyte nucleus, the karyosome. Checkpoint activation has also been l...

the purpose of this study was to analyze selected wolaita proverbs for their reflection of prejudiced negative images of femininity. the subjects used for the current study were 20 theme-relevant proverbs collected by interviewing systematically selected 12 elders and conducting participant-based observation. the qualitative research design was used to conduct this study. the result indicated t...

In amphibian and teleost embryos, the dorsal determinants (DDs) are believed to be initially localized to the vegetal pole and then transported to the prospective dorsal side of the embryo along a microtubule array. The DDs are known to activate the canonical Wnt pathway and thereby promote the expression of genes that induce the dorsal organizer. Here, by identifying the locus of the maternal-...

Sex determination in mammals has been defined as those events that fix the nature of the germ cell and the gonad, while other processes influencing sexual form and function such as hormone action constitute sex differentiation (Austin et al., 1981). Such determination involves the separation of germline and soma, controlled initially by maternal genes and then by the zygotic genome after fertil...