title: Detection and abundance of mRNA and protein encoded by transposable element activator (Ac) in maize.
abstract: The 3.5 kb long mRNA of the maize transposable element Ac contains an open reading frame (ORFa) which encodes a polypeptide of 807 amino acids, the putative transposase of Ac. The Ac mRNA is a rare transcript: we now estimate the fraction of Ac mRNA in wx-m7::Ac seedlings to be 2-13 x 10(-5) of the polyA RNA. Assuming that maize cells contain similar amounts of polyA RNA as another monocot (0.16 pg/cell), this is equivalent to 1.5-10 transcripts in each cell. A protein with an apparent molecular weight of 112 kDa is detected, by five antisera directed against different segments of ORFa, exclusively in nuclear extracts from Ac-containing maize. This protein is most likely the full-length Ac ORFa protein. We estimate its concentration to be in the range of 3 x 10(-7) of the nuclear proteins, or about 1000 molecules per triploid endosperm cell containing one Ac element.
authors.affiliation: Institut für Genetik, Universität zu Köln, Federal Republic of Germany.
authors.forename: H
authors.initials: H
authors.lastname: Fusswinkel
authors.forename: S
authors.initials: S
authors.lastname: Schein
authors.forename: U
authors.initials: U
authors.lastname: Courage
authors.forename: P
authors.initials: P
authors.lastname: Starlinger
authors.forename: R
authors.initials: R
authors.lastname: Kunze
mesh_terms: D015152:Blotting, Northern; D015153:Blotting, Western; D004251:DNA Transposable Elements; D008970:Molecular Weight; D009713:Nucleotidyltransferases / Q000235:genetics* / Q000378:metabolism; D016366:Open Reading Frames; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics*; D015183:Restriction Mapping; D014158:Transcription, Genetic; D019895:Transposases; D003313:Zea mays / Q000201:enzymology / Q000235:genetics*
chemical_list: D004251:DNA Transposable Elements; D012333:RNA, Messenger; D009713:Nucleotidyltransferases; D019895:Transposases