Sugar-responsible elements in the promoter of a gene for beta-amylase of sweet potato.
Expression of genes coding for sporamin and beta-amylase, the two most abundant proteins in storage roots of sweet potato, is coordinately inducible in atypical vegetative tissues by sugars. A sweet potato gene for beta-amylase (beta-Amy) with introns as well as a beta-Amy::GUS fusion gene composed of the beta-Amy promoter and the GUS coding sequence, both showed sugar-inducible expression in leaves of transgenic tobacco which occurred via a hexokinase-independent pathway. Analyses using various 5'-terminal and internal deletions of the beta-Amy promoter indicated that truncated promoters of beta-Amy containing a sequence between -901 and -820, relative to the transcription start site, and the basic promoter region can confer sugar-inducible expression. This 82 bp region contained the TGGACGG sequence that plays an essential role in the sugar-inducible expression of the truncated promoter of the sporamin gene. Deletion or base substitutions of this element in the truncated beta-Amy promoter abolished the sugar-inducible expression, the results suggesting that the TGGACGG element plays an important role in the coordinate induction of expression of genes for beta-amylase and sporamin by sugars.
Maeo
K
K
Department of Cellular Mechanisms and Functions, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Japan.
Tomiya
T
T
Hayashi
K
K
Akaike
M
M
Morikami
A
A
Ishiguro
S
S
Nakamura
K
K
D000595:Amino Acid Sequence; D001483:Base Sequence; D002241:Carbohydrates / Q000494:pharmacology*; D018744:DNA, Plant / Q000187:drug effects / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005966:Glucuronidase / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D030821:Plants, Genetically Modified / Q000235:genetics; D010947:Plants, Toxic; D011401:Promoter Regions, Genetic / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D020218:Response Elements / Q000235:genetics* / Q000502:physiology; D017384:Sequence Deletion; D012689:Sequence Homology, Nucleic Acid; D019657:Solanaceae / Q000201:enzymology / Q000235:genetics*; D014026:Nicotiana / Q000235:genetics; D001614:beta-Amylase / Q000235:genetics*
D002241:Carbohydrates; D018744:DNA, Plant; D011993:Recombinant Fusion Proteins; D001614:beta-Amylase; D005966:Glucuronidase