procera is a putative DELLA mutant in tomato (Solanum lycopersicum):: effects on the seed and vegetative plant
procera is a putative DELLA mutant in tomato (Solanum lycopersicum):: effects on the seed and vegetative plant
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DOI：
10.1093/jxb/erm354
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发表时间：
2008-02-01
影响因子：
6.9
通讯作者：
Bewley, J. Derek
中科院分区：
文献类型：
--
作者：
Bassel, George W.;Mullen, Robert T.;Bewley, J. Derek
番茄的procera（pro）突变体表现出良好的特征组成型赤霉酸（GA）反应表型。番茄DELLA基因LeGAI在前突变体背景中含有点突变，其导致LeGAI中保守的VHVID推定DNA结合结构域中的氨基酸改变为VHEID。相同的点突变在四种不同的遗传背景中表现出亲表型，表明该突变与亲表型共分离。由于转基因植物的不育性，突变体与组成型表达的野生型LeGAI基因序列的互补性尚不确定。前突变通过对腋芽发育的差异抑制改变番茄分枝结构，表明DELLA蛋白在调节植物结构中的作用。隔离gib-1亲双突变体胚轴，这是无法合成GA，发芽速度比野生型对应，发挥更大的胚胎生长潜力。因此，前突变调节番茄胚内的GA反应。LeGAI-GFP（绿色荧光蛋白）融合蛋白在洋葱表皮中的瞬时表达导致其定位于细胞核，并且该蛋白在GA存在下被蛋白酶体快速降解。
The procera (pro) mutant of tomato exhibits a well-characterized constitutive gibberellic acid (GA) response phenotype. The tomato DELLA gene LeGAI in the pro mutant background contains a point mutation that results in an amino acid change in the conserved VHVID putative DNA-binding domain in LeGAI to VHEID. This same point mutation is in four different genetic backgrounds exhibiting the pro phenotype, suggesting that this mutation co-segregates with the pro phenotype. Complementation of the mutant with a constitutively expressed wild-type LeGAI gene sequence was not conclusive due to the infertility of transgenic plants. The pro mutation alters tomato branching architecture through differential suppression of axillary bud development, indicating a role for DELLA proteins in the regulation of plant structure. Isolated gib-1 pro double mutant embryo axes, which are unable to synthesize GA, germinate faster than their wild-type counterparts, and exert greater embryo growth potential. The pro mutation is therefore regulating GA responses within the tomato embryo. Transient expression of a LeGAI-GFP (green fluorescent protein) fusion protein in onion epidermis results in its location to the nucleus, and this protein is rapidly degraded by the proteasome in the presence of GA.