Modulation of the cellulose content of tuber cell walls by antisense expression of different potato (Solanum tuberosum L.) CesA clones.
Four potato cellulose synthase (CesA) homologs (StCesA1, 2, 3 and 4) were isolated by screening a cDNA library made from developing tubers. Based on sequence comparisons and the fact that all four potato cDNAs were isolated from this single cDNA-library, all four StCesA clones are likely to play a role in primary cell wall biosynthesis. Several constructs were generated to modulate cellulose levels in potato plants in which the granule-bound starch synthase promoter was used to target the modification to the tubers. The StCesA3 was used for up- and down-regulation of the cellulose levels by sense (SE-StCesA3) and antisense (AS-StCesA3) expression of the complete cDNA. Additionally, the class-specific regions (CSR) of all four potato cellulose synthase genes were used for specific down-regulation (antisense) of the corresponding CesA genes (csr1, 2, 3 and 4). None of the transformants showed an overt developmental phenotype. Sections of tubers were screened for altered cell wall structure by Fourier Transform Infrared microspectroscopy (FTIR) and exploratory Principal Component Analysis (PCA), and those plants discriminating from WT plants were analysed for cellulose content and monosaccharide composition. Several transgenic lines were obtained with mainly decreased levels of cellulose. These results show that the cellulose content in potato tubers can be reduced down to 40% of the WT level without affecting normal plant development, and that constructs based on the CSR alone are specific and sufficient to down-regulate cellulose biosynthesis.
Oomen
Ronald J F J
RJ
Graduate School Experimental Plant Sciences, Laboratory of Plant Breeding, Wageningen University, Binnenhaven 5, 6709 PD Wageningen, The Netherlands.
Tzitzikas
Emmanouil N
EN
Bakx
Edwin J
EJ
Straatman-Engelen
Irma
I
Bush
Maxwell S
MS
McCann
Maureen C
MC
Schols
Henk A
HA
Visser
Richard G F
RG
Vincken
Jean-Paul
JP
D002473:Cell Wall / Q000378:metabolism*; D002482:Cellulose / Q000096:biosynthesis* / Q000378:metabolism; D003124:Colorimetry; D018076:DNA, Complementary / Q000235:genetics; D015870:Gene Expression; D005964:Glucosyltransferases / Q000235:genetics* / Q000378:metabolism; D009005:Monosaccharides / Q000737:chemistry; D005810:Multigene Family; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D016372:RNA, Antisense / Q000096:biosynthesis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D011198:Solanum tuberosum / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D017550:Spectroscopy, Fourier Transform Infrared; D014170:Transformation, Genetic
D018076:DNA, Complementary; D009005:Monosaccharides; D010940:Plant Proteins; D016372:RNA, Antisense; D002482:Cellulose; D005964:Glucosyltransferases