Ethanol exposure affects cell movement during gastrulation and induces split axes in zebrafish embryos.
To explore the toxic effects of ethanol on axis formation during embryogenesis, zebrafish embryos at different developmental stages were treated with 3% ethanol for 3h. The effects of ethanol exposure appeared to be stage-dependent. The dome stage embryo was most sensible to form posterior split axes upon ethanol exposure. Morphological and histological observations and whole-mount in situ hybridization results showed that ethanol exposure at this stage caused a general gastrulation delay, and induced double notochords, double neural tubes and two sets of somites in the posterior trunk. Mechanistically, no ectopic organizer was found by examining the expression patterns of dorsoventral markers including goosecoid, chordin and eve1 at the onset of gastrulation. However, radial intercalation, epiboly and convergence extension were inhibited by ethanol exposure as revealed by cell labeling, phenotypic observation and the expression patterns of axial or paraxial markers. Further investigation showed that the cell aggregation might be affected by ethanol exposure, as indicated by the much more scattered expression pattern of chordin, eve1 and wnt11 at the early gastrula stage, and the discontinuous gsc positive cells during migration. These results imply that ethanol might affect cell movement before and during gastrulation and as a consequence, induces a split axes phenotype.
Zhang
Ying
Y
Institute of Developmental Biology, College of Life Science, Key Lab of Experimental Teratology of Ministry of Education, Shandong University, 27 Shanda South Road, Jinan, Shandong 250100, China. zhangying9268@163.com
Shao
Ming
M
Wang
Lifeng
L
Liu
Zhongzhen
Z
Gao
Ming
M
Liu
Chao
C
Zhang
Hongwei
H
D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism; D019521:Body Patterning / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects*; D004625:Embryo, Nonmammalian / Q000187:drug effects / Q000378:metabolism; D000431:Ethanol / Q000494:pharmacology*; D005326:Fetal Proteins; D054262:Gastrulation / Q000187:drug effects*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D017403:In Situ Hybridization; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D013045:Species Specificity; D020825:T-Box Domain Proteins / Q000235:genetics / Q000378:metabolism; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics / Q000378:metabolism; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism; D000098908:Brachyury Protein
D051792:Basic Helix-Loop-Helix Proteins; D000431:Ethanol; D005326:Fetal Proteins; D009419:Nerve Tissue Proteins; D020825:T-Box Domain Proteins; D029961:Zebrafish Proteins; D000098908:Brachyury Protein; C486337:neurog1 protein, zebrafish