ISSN:
1617-4623
Keywords:
Transposase
;
DNA-binding protein
;
Zea mays
;
mobile DNA
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary 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 × 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 × 10− of the nuclear proteins, or about 1000 molecules per triploid endosperm cell containing one Ac element.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00269846