TY  - JOUR
A1  - Wike, Candice L.
A1  - Guo, Yixuan
A1  - Tan, Mengyao
A1  - Nakamura, Ryohei
A1  - Shaw, Dana Klatt
A1  - Díaz, Noelia
A1  - Whittaker-Tademy, Aneasha F.
A1  - Durand, Neva C.
A1  - Aiden, Erez Lieberman
A1  - Vaquerizas, Juan M.
A1  - Grunwald, David
A1  - Takeda, Hiroyuki
A1  - Cairns, Bradley R.
T1  - Chromatin architecture transitions from zebrafish sperm through early embryogenesis
Y1  - 2021/06/01 
JF  - Genome Research 
JO  - Genome Research 
SP  - 981 
EP  - 994 
DO  - 10.1101/gr.269860.120 
VL  - 31 
IS  - 6 
UR  - http://genome.cshlp.org/content/31/6/981.abstract 
N2  - Chromatin architecture mapping in 3D formats has increased our understanding of how regulatory sequences and gene expression are connected and regulated in a genome. The 3D chromatin genome shows extensive remodeling during embryonic development, and although the cleavage-stage embryos of most species lack structure before zygotic genome activation (pre-ZGA), zebrafish has been reported to have structure. Here, we aimed to determine the chromosomal architecture in paternal/sperm zebrafish gamete cells to discern whether it either resembles or informs early pre-ZGA zebrafish embryo chromatin architecture. First, we assessed the higher-order architecture through advanced low-cell in situ Hi-C. The structure of zebrafish sperm, packaged by histones, lacks topological associated domains and instead displays “hinge-like” domains of ∼150 kb that repeat every 1–2 Mbs, suggesting a condensed repeating structure resembling mitotic chromosomes. The pre-ZGA embryos lacked chromosomal structure, in contrast to prior work, and only developed structure post-ZGA. During post-ZGA, we find chromatin architecture beginning to form at small contact domains of a median length of ∼90 kb. These small contact domains are established at enhancers, including super-enhancers, and chemical inhibition of Ep300a (p300) and Crebbpa (CBP) activity, lowering histone H3K27ac, but not transcription inhibition, diminishes these contacts. Together, this study reveals hinge-like domains in histone-packaged zebrafish sperm chromatin and determines that the initial formation of high-order chromatin architecture in zebrafish embryos occurs after ZGA primarily at enhancers bearing high H3K27ac. 
ER  -