拟南芥抗生长素突变体axr1-12的抑制型突变体筛选(英文)

Suppressor Screening with an Auxin-resistant Mutant axr1-12 of Arabidopsis thaliana

利用抗生长素突变体axr1-12筛选获得了对生长素敏感并且果荚发育良好的突变体38个,对其中的两个非等位隐性突变体sa1和sa2进行了分析。新突变体sa1和sa2在叶形、株型、以及根系生长对生长素的反应等方面都在一定程度上表现出与原突变体axr1-12相反的特征。sa1和sa2还使axr1-12的果荚发育缺陷得到了修复,但其种子发育表现异常。sa1的果荚中可见种子和无胚的种子状结构,在sa2的果荚中则同时存在部分健康种子和发育不良的胚珠。结果显示,sa1和sa2编码的蛋白质可能参与果荚对生长素的反应,sa1还可能在受精前种子发育初级阶段起调控作用。

axr1-12 was used as the original mutant to screen secondary mutants those were more sensitive to auxin and could develop siliques apparently. 38 mutants were isolated and two un-allelic recessive suppressor, sal and sa2, were characterized. Results showed that mutations in sal and sa2 altered the leaf shape and the plant posture, and suppressed axr1-12 in root response to 2,4-D. sal and sa2 also recovered the defect of axr1-12 in silique. However, abnormal seed development was observed in these two mutants. Siliques of sal developed both seeds and seed-like structures with no embryos, while siliques of sa2 had seed setting partially and some ovules arrested in the full-grown siliques. Results suggest that proteins coded by sal and sa2 might change the response of siliques to auxin, and sal may play roles in controlling initiation of seed development before fertilization.