Asymmetric Localization of Ck2ÃÂ± During Xenopus Oogenesis
Gregory A. Imbrie, Hao Wu, David C. Seldin and Isabel Dominguez*
Hematology-Oncology Section, Department of Medicine, Boston University Medical School, 650 Albany Street, Boston, MA, USA
- *Corresponding Author:
- Isabel Dominguez
Department of Medicine
Boston University Medical School
650 Albany Street, Boston, MA, USA
E-mail: [email protected]
Received Date: February 22, 2012; Accepted Date: May 02, 2012; Published Date: May 05, 2012
Citation: Imbrie GA, Wu H, Seldin DC, Dominguez I (2012) Asymmetric Localization of Ck2α During Xenopus Oogenesis . Human Genet Embryol S4:001. doi: 10.4172/2161-0436.S4-001
Copyright: © 2012 Sofocleous C, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
The establishment of the dorso-ventral axis is a fundamental process that occurs after fertilization. Dorsal axis specification in frogs starts immediately after fertilization, and depends upon activation of Wnt/β-catenin signaling. The protein kinase CK2α can modulate Wnt/β-catenin signaling and is necessary for dorsal axis specification in Xenopus laevis. Our previous experiments show that CK2α transcripts and protein are animally localized in embryos, overlapping the region where Wnt/β-catenin signaling is activated. Here we determined whether the animal localization of CK2α in the embryo is preceded by its localization in the oocyte. We found that CK2α transcripts were detected from stage I, their levels increased during oogenesis, and were animally localized as early as stage III. CK2α transcripts were translated during oogenesis and CK2α protein was localized to the animal hemisphere of stage VI oocytes. We cloned the CK2α 3’UTR and showed that the 2.8 kb CK2α transcript containing the 3’UTR was enriched during oogenesis. By injecting ectopic mRNAs, we demonstrated that both the coding and 3’UTR regions were necessary for proper CK2α transcript localization. This is the first report showing the involvement of coding and 3’UTR regions in animal transcript localization. Our findings demonstrate the pre-localization of CK2α transcript and thus, CK2α protein, in the oocyte. This may help restrict CK2α expression in preparation for dorsal axis specification.