Biology Reference
In-Depth Information
DELLAs Repress the Expression of MYB21, MYB24, and
MYB57
Three MYB genes, namely MYB21, MYB24 and MYB57, were among the identi-
fied DELLA-repressed stamen-enriched genes (Figure 1; Table 1). Based on the
phylogenetic tree, MYB24 and MYB21 are classified into the subgroup 19 of
R2R3-MYB family [36]. MYB57 shares high similarity with this subfamily and
is a close member to this subfamily [37]. Overall, MYB21 shares 61.6% and
51.0% identity with MYB24 and MYB57 at the amino acid level, respectively.
The expression of these three MYBs in the young flower buds were reduced to a
very low level in ga1-3 but restored to the wild type (WT) level in the ga1-3 gai-t6
rga-t1 rgl1-1 rgl2-1 penta mutant (Figure 2A). In order to find out which DELLA
(RGL1, RGL2, RGA and GAI) is more effective in repressing the expression of
Figure 2.
MYB21, MYB24I, and MYB57 Are RGA- and RGL2-Repressible Floral Specific Genes.
(A) RT-PCR
analysis shows that the expression of the three MYB genes in the young flower buds are greatly
reduced in ga1-3 but restored to the WT level in ga1-3 gai-t6 rgat2 rgl1-1 rgl2-1 (penta). (B-C) RT-PCR
analysis shows that the repressed expression of the three MYB genes in ga1-3 was restored in ga1-3 gai-t6 rga-t2
rgl2-1 (Q2) and ga1-3 rga-t2 rgl1-1 rgl2-1 (Q4) two quadruple mutants but not in ga1-3 gai-t6 rgl1-1 rgl2-1
(Q1) and ga1-3 gai-t6 rga-t2 rgl1-1 (Q3) two quadruple mutants (B). This restoration of MYB expression nicely
correlates with the recovery of fertility in Q2 and Q4 (C). Total RNA used in RT-PCR analysis was extracted
from the young flower buds. (D) RT-PCR analysis shows that the three MYB genes are floral specific genes.
IF, inflorescence; CL, cauline leaves; RL, rosette leaves; IT, internodes; RT, roots; SL, siliques. (E) Amino acid
alignment of MYB21, MYB24 and MYB57 proteins. The conserved R2 and R3 domains and the NYWSV/ME/
DDlWP/S motif are highlighted in red, blue and green, respectively.
