Vol. 153: 1321–1331
Smykowski A., Zimmermann P., and Zentgraf U. G-Box Binding Factor1 Reduces CATALASE2 Expression and Regulates the Onset of Leaf Senescence in Arabidopsis.
In the legend of Figure 2, it was stated that the error bars indicate the sd, but actually the se was presented. Furthermore, the indicated P values were incorrect. The correct values of one-sample t tests are P = 0.0092 for the top bar chart (A) and P = 0.0066 for the bottom bar chart (B). The corrected Figure 2 is presented below.
Figure 6.
Phenotype of Col-0 and gbf1 mutant plants. A, Rosette leaves of 6.5-week-old plants and 8-week-old plants sorted from young to old leaves within the rosette using a color code. Photographs of upside-down rosettes are shown on the right side. B, Development of plants from 4 to 7 weeks. C, Proportion of leaves categorized in four groups according to their leaf color (fully green, green-yellow, fully yellow, brown and dry) of seven to 10 plants for each line derived from two to four independent plant growth series. Error bars indicate sd; asterisks indicate significant differences from Col-0 (t test, P < 0.05).
In addition, the images presented in the original version of Figure 6 were not presented correctly, and as a result, the images of the 8.5-week-old plants did not correspond to the plant lines indicated. In the corrected Figure 6, presented below, the pictures are replaced by the correct pictures of 8-week-old plants, and a categorization of leaves of seven to 10 plants grown in two to four independent plant growth series was added in order to confirm the phenotype. The gbf1-ex line was significantly delayed in senescence. The gbf1-int line also was delayed in senescence, but the difference was less significant since in this case only the number of brown/dry leaves in 8-week-old plants showed a significant difference to Columbia-0 (Col-0) according to t test (P < 0.05). However, this difference correlates to the expression level of GBF1 since gbf1-ex is a knockout whereas gbf1-int is only a knockdown T-DNA insertion line.
Furthermore, in the legend of Figure 7, there was a contradiction in stating that three independent experiments were performed for the expression analyses and in the last sentence’s statement that the error bars indicated the sd of five independent experiments. Here, n = 3 is correct. A corrected Figure 7 is provided below that includes statistics of the differences in expression. Lowercase letter a denotes significant differences compared with expression levels in 4-week-old Col-0 plants, whereas lowercase letter b denotes significant differences from the expression level in Col-0 plants of the same age. Thus, RBCS1a expression is significantly reduced, whereas SAG12 and WRKY53 expression is significantly induced in 8-week-old Col-0 plants compared with 4-week-old Col-0 plants. These effects cannot be observed in the mutant lines. SAG12 induction is significantly lower in 8-week-old gbf1-ex plants compared with 8-week-old Col-0 plants, and RBCS1a reduction is significantly lower in 8-week-old gbf1-int plants compared with 8-week-old Col-0 plants.
Figure 7.
Gene expression analyses. Expression of GBF1, WRKY53, RBCS1a, and SAG12 in 4-, 6-, and 8-week-old Col-0 and gbf1-ex and gbf1-int was examined by semiquantitative RT-PCR. ACTIN2 was used as a control for equal amounts of cDNA. A, One example of an agarose gel. B, Quantification of expression analyses of three independent experiments are presented. ACTIN2 was used for normalization; error bars indicate sd of three independent experiments. Lowercase letter a denotes significant differences from 4-week-old Col-0 expression levels (t test, P < 0.05). Lowercase letter b denotes significant differences from Col-0 values of the same age (t test, P < 0.05).
On Page 1325 in the right column on line 9, “8.5-week-old plants” should be “8-week-old plants.”
All conclusions drawn from the data are still valid.
New figure legends:
Figure 2.
Transient transformation assays. A, Tobacco leaves were coinfiltrated with A. tumefaciens transformed with a CAT2:GUS construct and A. tumefaciens containing either an empty 35S plant expression vector as control or a 35S:GBF1 expression vector. GUS activity levels in control transformations were set to 100%. Sixteen independent experiments were performed. The error bars indicate se (one-sample t test, P = 0.0092). B, Arabidopsis protoplasts were cotransformed with a CAT2:GUS reporter construct and either an empty 35S plant expression vector as control or a 35S:GBF1 expression vector. GUS activity levels in control transformations were set to 100%. Protoplasts were prepared for transformation three times; nine independent transformation experiments were performed. Error bars indicate se (one-sample t test, P = 0.0066). Asterisks indicate significant differences, P < 0.01.