Cloning of upstream sequences responsible for cell cycle regulation of the Nicotiana sylvestris CycB1;1 gene.
To understand the mechanisms involved in the regulation of the mitotic cyclin B Nicta; CycB1;1 expression, we have cloned the Nicotiana sylvestris cyclin gene, Nicsy; CycB1;1, whose coding sequence is homologous to that of Nicta;CycB1;1 cDNA. The structure and the function of its 5'-flanking region, 1149 bp upstream of the first start codon, was analysed. By producing stably transformed cells of a synchronized culture with the Nicsy;CycB1;1 promoter/beta-glucuronidase (gus) reporter gene fusion, we demonstrate that the 1149 bp promoter fragment mediates a gus transcriptional oscillation, indistinguishable from that of endogenous Nicsy;CycB1;1 cyclin B transcripts. Transient GUS activity in BY-2 protoplasts reveals that promoter activity is considerably reduced by shortening the 5'-flanking region to 538 or 320 bp. Furthermore, the 320 bp fragment no longer mediates the observed transcriptional regulation of the 1149 bp Nicsy;CycB1;1 promoter in BY-2 protoplasts isolated from synchronized cells.
Tréhin
C
C
Institut de Biotechnologie des Plantes, Université Paris-Sud, Orsay, France.
Ahn
I O
IO
Perennes
C
C
Couteau
F
F
Lalanne
E
E
Bergounioux
C
C
D002453:Cell Cycle / Q000235:genetics*; D002478:Cells, Cultured; D003001:Cloning, Molecular; D019926:Cyclin B / Q000235:genetics*; D056744:Cyclin B1; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D017930:Genes, Reporter / Q000235:genetics; D005966:Glucuronidase / Q000235:genetics; D008969:Molecular Sequence Data; D010947:Plants, Toxic; D011401:Promoter Regions, Genetic / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D018749:RNA, Plant / Q000032:analysis; D011993:Recombinant Fusion Proteins; D015183:Restriction Mapping; D017422:Sequence Analysis, DNA; D014026:Nicotiana / Q000235:genetics*
D019926:Cyclin B; D056744:Cyclin B1; D012333:RNA, Messenger; D018749:RNA, Plant; D011993:Recombinant Fusion Proteins; D005966:Glucuronidase