Embryonic stages from cleavage to gastrula in the loach Misgurnus anguillicaudatus.
Early developmental staging from the zygote stage to the gastrula is a basic step for studying embryonic development and biotechnology. We described the early embryonic development of the loach, Misgurnus anguillicaudatus, based on morphological features and gene expression. Synchronous cleavage was repeated for 9 cycles about every 27 min at 20 degrees C after the first cleavage. After the 10th synchronous cleavage, asynchronous cleavage was observed 5.5 h post-fertilization (hpf), indicating the mid-blastula transition. The yolk syncytial layer (YSL) was formed at this time. Expressions of goosecoid and no tail were detected by whole-mount in situ hybridization from 6 hpf. This time corresponded to the late-blastula period. Thereafter, epiboly started and a blastoderm covered over the yolk cell at 8 hpf. At 10 hpf, the germ ring and the embryonic shield were formed, indicating the stage of early gastrula. Afterward, the epiboly advanced at the rate of 10% of the yolk cell each hour. The blastoderm covered the yolk cell completely at 15 hpf. The embryonic development of the loach resembled that of the zebrafish in terms of morphological change and gene expression. Therefore, it is possible that knowledge of the developmental stages of the zebrafish might be applicable to the loach.
Laboratory of Breeding Science, Graduate School of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Japan. motchan@fish.hokudai.ac.jp
Takafumi
T
Fujimoto
Takashi
T
Kataoka
Satoshi
S
Otani
Taiju
T
Saito
Takanori
T
Aita
Etsuro
E
Yamaha
Katsutoshi
K
Arai
D019342:Acetic Acid; D000818:Animals; D002970:Cleavage Stage, Ovum / Q000166:cytology*; D003531:Cypriniformes / Q000196:embryology* / Q000378:metabolism; D005557:Formaldehyde; D005775:Gastrula / Q000166:cytology*; D018507:Gene Expression Regulation, Developmental; D051956:Goosecoid Protein; D018398:Homeodomain Proteins / Q000378:metabolism; D017403:In Situ Hybridization; D010851:Picrates; D012097:Repressor Proteins / Q000378:metabolism; D020825:T-Box Domain Proteins / Q000378:metabolism; D013997:Time Factors; D014157:Transcription Factors / Q000378:metabolism
D051956:Goosecoid Protein; D018398:Homeodomain Proteins; D010851:Picrates; D012097:Repressor Proteins; D020825:T-Box Domain Proteins; D014157:Transcription Factors; D005557:Formaldehyde; C026239:Bouin's solution; D019342:Acetic Acid