title: RNA synthesised during oogenesis and early embryogenesis in an insect egg (Euscelis plebejus).
abstract: RNA labelled during oogenesis or early embryogenesis was isolated from eggs of the leaf hopperEuscelis plebejus. The polyadenylated RNA fraction deposited during early oogenesis accounted for approximately 2.7% of the total RNA content of the newly laid egg. This fraction differed significantly in molecular weight (15-32 S) from poly(A)-containing RNA synthesised between early cleavage and early germ anlage stages (4-20S). Locally injected3H-uridine spread through the egg within approximately 3 h. A considerable fraction (25-35%) of label injected as3H-uridine during early cleavage was recovered in DNA at subsequent stages (10-20 h later); labelled RNA was not found prior to the cellular blastoderm stage. When the yolk-endoplasm was separated from the blastoderm cells, only the latter contained demonstrable amounts of RNA synthesised by the embryo. Of the precursor incorporated into embryonic RNA, approximately 10% was found in the polyadenylated fraction at the early blastoderm stage, but only 3% at the early germ anlage stage. No differences in size distribution of polyadenylated RNA were evident between anterior and posterior halves of the early germ anlage stage.
authors.affiliation: Biologisches Institut I (Zoologie) der Albert-Ludwig-Universität, Albertstr. 21a, D-7800, Freiburg i.Br., Federal Republic of Germany.
authors.forename: Otto
authors.initials: O
authors.lastname: Schmidt
authors.affiliation: Biologisches Institut I (Zoologie) der Albert-Ludwig-Universität, Albertstr. 21a, D-7800, Freiburg i.Br., Federal Republic of Germany.
authors.forename: Herbert
authors.initials: H
authors.lastname: Jäckle
keywords: 3H-uridine precursor conversion; Insect embryogenesis; Maternal RNA; Polyadenylated RNA