title: Polyadenylated mRNAs from various developmental stages of Xenopus laevis. Role of 26 S mRNA.
abstract: In Xenopus laevis embryos, the 26 S polyadenylated mRNA, coding for the myosin heavy chain, shows a maximum relative concentration as measured by the 3H-poly(U)-hybridization technique, at the neural-plate stage (st. 12.5 of Nieuwkoop and Faber, [NF]) only in the dorsal (ectodermal and mesodermal) region, i.e. shortly before the morphological appearance of the somites. On the contrary, myosin-heavy-chain mRNA cannot be observed in the ventral region with the same technique. This 26 S mRNA begins to be hybridizable at the gastrula stage (st. 10 NF). Polyadenylated mRNAs from postgastrula stages were translated in a cell-free system of rabbit reticulocytes, and the translation products were analyzed by polyacrylamide-gel electrophoresis and immunoprecipitation. It was found that protein recognizable as the heavy chain of the muscle myosin had been translated. Its possible role on the induction of somites is discussed.
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000187:drug effects / Q000502:physiology; D003609:Dactinomycin / Q000494:pharmacology; D004625:Embryo, Nonmammalian / Q000502:physiology; D005260:Female; D005775:Gastrula / Q000502:physiology; D008970:Molecular Weight; D009693:Nucleic Acid Hybridization; D011061:Poly A / Q000235:genetics* / Q000302:isolation & purification; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics* / Q000302:isolation & purification; D011817:Rabbits; D012156:Reticulocytes / Q000378:metabolism; D014981:Xenopus
chemical_list: D012333:RNA, Messenger; D003609:Dactinomycin; D011061:Poly A