Role of structural domains for maize gamma-zein retention in Xenopus oocytes.
In order to examine the role of cysteine (Cys)-rich domains in the accumulation of maize (Zea mays L.) gamma-zein within the endoplasmic-reticulum-derived protein bodies, we studied the localization of gamma-zein and of two truncated forms of gamma-zein in Xenopus laevis oocytes. The two derivatives were constructed from a DNA encoding the gamma-zein: one by deletion of the Pro-X linker region (21 amino acids) and the other by deletion of the Cys-rich domain (94 amino acids). In-vitro-synthesized transcripts were injected into oocytes and the distribution of the translation products was then analyzed. The entire gamma-zein and both truncated forms of the gamma-zein had accumulated efficiently in microsomes and no traces of secretion were observed. We suggest that neither C-terminal Cys-rich nor Pro-X domains are essential for gamma-zein retention in oocyte vesicles. Therefore, structural features derived from disulphide bonds are not necessary for gamma-zein targeting on the endoplasmic reticulum.
Torrent
M
M
Departament de Genètica Molecular, Centre de Investigació i Desenvolupament (CSIC), Barcelona, Spain.
Geli
M I
MI
Ruiz-Avila
L
L
Canals
J M
JM
Puigdomènech
P
P
Ludevid
D
D
D000595:Amino Acid Sequence; D000818:Animals; D001692:Biological Transport; D003001:Cloning, Molecular; D003545:Cysteine / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000378:metabolism; D005260:Female; D008861:Microsomes / Q000378:metabolism; D008969:Molecular Sequence Data; D009865:Oocytes; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism; D011392:Proline / Q000378:metabolism; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D014982:Xenopus laevis; D003313:Zea mays; D015028:Zein / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D010446:Peptide Fragments; D011994:Recombinant Proteins; D015028:Zein; D011392:Proline; D003545:Cysteine