highly asynchronous and asymmetric cleavage divisions accompany early transcriptional activity in pre-blastula medaka embryos高度异步和乳沟不对称分裂伴随早期转录活动pre-blastula青鳉的胚胎.pdfVIP

Highly Asynchronous and Asymmetric Cleavage Divisions Accompany Early Transcriptional Activity in Pre-Blastula Medaka Embryos . . Michael Kraeussling , Toni Ulrich Wagner* , Manfred Schartl Abstract In the initial phase of development of fish embryos, a prominent and critical event is the midblastula transition (MBT). Before MBT cell cycle is rapid, highly synchronous and zygotic gene transcription is turned off. Only during MBT the cell cycle desynchronizes and transcription is activated. Multiple mechanisms, primarily the nucleocytoplasmic ratio, are supposed to control MBT activation. Unexpectedly, we find in the small teleost fish medaka (Oryzias latipes) that at very early stages, well before midblastula, cell division becomes asynchronous and cell volumes diverge. Furthermore, zygotic transcription is extensively activated already after the 64-cell stage. Thus, at least in medaka, the transition from maternal to zygotic transcription is uncoupled from the midblastula stage and not solely controlled by the nucleocytoplasmic ratio. Citation: Kraeussling M, Wagner TU, Schartl M (2011) Highly Asynchronous and Asymmetric Cleavage Divisions Accompany Early Transcriptional Activity in Pre- Blastula Medaka Embryos. PLoS ONE 6(7): e21741. doi:10.1371/journal.pone.0021741 Editor: Carl-Philipp Heisenberg, Institute of Science and Technology Austria, Austria Received November 29, 2010; Accepted June 10, 2011; Published July 7, 2011 Copyright: 2011 Kraeussling 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. Funding: This study was supported by German Research