Please use this identifier to cite or link to this item:
Title: Three high-lysine mutations control the level of ATP-binding HSP70-like proteins in the maize endosperm
Authors: Marocco, A.
Santucci, Annalisa 
Cerioli, S.
Motto, M.
Di Fonzo, N.
Thompson, R.
Salamini, F.
Issue Date: 1991
Project: None 
The synthesis and deposition of seed storage proteins in maize are affected by several dominant and recessive mutants. The effect of three independent mutations, floury-2 (fl2), Defective endosperm-B30 (De-B30), and Mucronate (Mc), that reduce zein level in the endosperm were investigated. These mutations also control the level of b-70, a polypeptide bound to protein bodies, which is separable into the two isoforms b-70I and b-70II by two-dimensional gel electrophoresis. Both isoforms are overexpressed 10-fold in fl2; however, only b-70I is present in De-B30 and Mc, which contain an amount of total b-70 isoforms fivefold higher than in the wild type. Both b-70I and b-70II resemble heat shock protein (HSP70) in that they bind ATP, cross-react with anti-HSP antibodies, and have N-terminal sequence homology to HSP70. All maize protein body-located b-70 characteristics are typical of those of chaperone-like HSPs. A third protein, b-70III, similar in size to but slightly more acidic than b-70I and b-70II, also binds ATP and reacts with the same antibody, providing evidence for the presence in endosperm extracts of a cytosolic chaperone-like protein. The level of b-70III was not altered by the mutations studied. The results suggested that the repression effect of the three mutations on zein accumulation may be mediated by the alteration of a zein transport or zein assembly process involving b-70I and b-70II.
ISSN: 1040-4651
Appears in Collections:Publications

Show full item record

Google ScholarTM


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.