Temporal and spatial expression of TGF-beta2 in chicken somites during early embryonic development.
A multifunctional growth and differentiation factor TGF-beta is expressed at various developmental stages, and its principle role may be involvement in organogenesis. The present study was performed to evaluate the temporal and spatial expression of TGF-beta2 mRNA in developing somites of chicken embryos during their early developmental periods. TGF-betas were expressed in various tissues of the whole embryo obtained at stage 26 (5 days of incubation) as revealed by whole-mount in situ hybridization. TGF-beta2 mRNA was predominantly expressed in somites as well as the head, branchial arch, wing buds, and leg buds. TGF-beta2 mRNA first appeared in the rostral somites on E4, and its expression sites expanded to the middle range of somites at stage 26. At stages 29-31 (6-7 days), expression in the rostral somites disappeared, and it appeared in the caudal somites. TGF-beta2 expression was also analyzed in sections of the embryo by in situ hybridization. The expression sites of TGF-beta2 were clearly observed in the myotomal somite tips as well as the neural tube. RT-PCR analysis showed that TGF-beta2 expression was very low in the blastocyte stage embryo and thereafter increased linearly in the whole trunk until stage 26. These data indicate that TGF-beta2 may be a regulatory factor participating in the somitogenesis of chicken embryos.
Aramaki
Shinya
S
Laboratory of Reproductive Physiology and Biotechnology, Department of Animal and Marine Bioresource Sciences, Graduate School Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581, Japan.
Sato
Fuminori
F
Soh
Tomoki
T
Yamauchi
Nobuhiko
N
Sakai
Takafumi
T
Hattori
Masa-Aki
MA
D000367:Age Factors; D000818:Animals; D002642:Chick Embryo / Q000196:embryology* / Q000378:metabolism*; D017931:DNA Primers; D018076:DNA, Complementary / Q000235:genetics; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D006652:Histological Techniques; D017403:In Situ Hybridization; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019170:Somites / Q000378:metabolism*; D016212:Transforming Growth Factor beta / Q000378:metabolism*; D053781:Transforming Growth Factor beta2
D017931:DNA Primers; D018076:DNA, Complementary; D016212:Transforming Growth Factor beta; D053781:Transforming Growth Factor beta2