Promoter analysis of the chalcone synthase (chsA) gene of Petunia hybrida: a 67 bp promoter region directs flower-specific expression.
In order to scan the 5' flanking region of the chalcone synthase (chs A) gene for regulatory sequences involved in directing flower-specific and UV-inducible expression, a chimaeric gene was constructed containing the chs A promoter of Petunia hybrida (V30), the chloramphenicol acetyl transferase (cat) structural sequence as a reporter gene and the chs A terminator region of Petunia hybrida (V30). This chimaeric gene and 5' end deletions thereof were introduced into Petunia plants with the help of Ti plasmid-derived plant vectors and CAT activity was measured. A 220 bp chs A promoter fragment contains cis-acting elements conferring flower-specific and UV-inducible expression. A promoter fragment from -67 to +1, although at a low level, was still able to direct flower-specific expression but could not drive UV-inducible expression in transgenic Petunia seedlings. Molecular analysis of binding of flower nuclear proteins to chs A promoter fragments by gel retardation assays showed strong specific binding to the sequences from -142 to +81. Promoter sequence comparison of chs genes from other plant species, combined with the deletion analysis and gel retardation assays, strongly suggests the involvement of the TACPyAT repeats (-59 and -52) in the regulation of organ-specificity of the chs A gene in Petunia hybrida. We also describe an in vitro organ-specific transient expression system, in which flower or purple callus protoplasts are used, that enables us to pre-screen organ-specific expression of a chimaeric reporter gene.
van der Meer
I M
IM
Department of Genetics, Vrije Universiteit, Amsterdam, Netherlands.
Spelt
C E
CE
Mol
J N
JN
Stuitje
A R
AR
D000217:Acyltransferases / Q000235:genetics*; D001483:Base Sequence; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics; D002872:Chromosome Deletion; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic / Q000528:radiation effects; D005818:Genetic Engineering; D008969:Molecular Sequence Data; D009154:Mutation; D009928:Organ Specificity; D010944:Plants / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012091:Repetitive Sequences, Nucleic Acid; D014466:Ultraviolet Rays
D012333:RNA, Messenger; D004247:DNA; D000217:Acyltransferases; D015500:Chloramphenicol O-Acetyltransferase; C020141:flavanone synthetase