Biology Reference
In-Depth Information
Arabidopsis root growth by delaying the GA-induced destabilization of DELLA
[48]. Recently, the complexity of interactions between ethylene and GA signal
transduction pathways were analyzed by using combinations of different ethyl-
ene and GA related mutants [49]. Hormone-hormone interaction also plays an
important role in controlling flowering. For example, it was found that stress in-
duced hormone ethylene control floral transition via DELLA-dependent regula-
tion of floral meristem-identity genes LEAFY and SUPPRESSOR OF OVEREX-
PRESSION OF CONSTANS 1 (SOC1) [50]. We have here established a linear
relationship between GA and JA in that GA modulates the expression of DAD1
that in a likely scenario to promote JA biosynthesis and in return JA induces the
expression of MYB21, MYB24 and MYB57 to control the normal stamen devel-
opment in Arabidopsis.
Materials and Methods
Plant Materials
Plants were grown as described previously [19]. Mutant lines (La-er background)
ga1-3, Q3 (ga1-3 gai-t6 rga-t2 rgl1-1) and penta (ga1-3 gai-t6 rga-t2 rgl1-1
rgl2-1) were described previously [8]. Mutant lines (Col-0 background) myb21-
t1 (SALK_042711), myb24-t1 (SALK_017221) and myb57-t1 (SALK_065776)
were obtained from Arabidopsis Biological Resource Centre at the Ohio State
University [51] and verified using primer pairs listed in Table 3. These lines were
backcrossed twice to purify the genetic background and were then used for all
experiments described in this paper. Double mutants were generated from crosses
between the relevant single mutants. Triple mutant myb21-t1 myb24-t1 myb57-
t1 was obtained from cross between myb21-t1 myb24-t1 and myb24-t1 myb57-
t1. Hexa1 (ga1-3 gai-t6 rga-t2 rgl1-1 rgl2-1 myb21-t1), hexa2 (ga1-3 gai-t6 rga-
t2 rgl1-1 rgl2-1 myb24-t1) and hepta (ga1-3 gai-t6 rga-t2 rgl1-1 rgl2-1 myb21-t1
myb24-t1) mutants were in Laer background via cross-pollination of myb21-t1
myb24-t1 to the ga1-3 gai-t6 rga-t2 rgl1-1 rgl2-1 penta mutant four times. SEM
of the penta, hexa1, hexa2 and hepta mutants was performed as described previ-
ously [8]. The opr3 mutant is in the Ws background [6].
Table 3.
Primer pairs used for genotyping MYB mutants.
