---

作 者 ：曾后清, 朱毅勇, 包勇, 沈其荣, 郭凯, 黄思齐, 杨志敏

期 刊 ：植物营养与肥料学报 2010年 16卷 1期 页码：166-171

关键词：番茄；侧根；生长素；miRNA；NAC1；

Keywords:auxin, miRNA, NAC1,

摘 要 ：为了研究番茄幼苗在缺磷胁迫下根系形态发育与生长素、生长素信号转导途径中的转录因子NAC1，以及调控NAC1 表达的上游miR164之间的关系。试验以5和500 μmol/L磷浓度作为缺磷胁迫和对照，检测了外源生长素NAA（1-naphthalene acetic acid）及生长素抑制剂NPA（N-1-naphthylphthalamic acid）对侧根形成的影响； 同时采用RT-PCR检测了NAC1和miR164在缺磷胁迫下的时序表达。结果表明，缺磷胁迫下侧根大量形成与生长素及其运输密切相关，在侧根迅速形成的24 h内，NAC1的表达在缺磷胁迫下增强； 而其上游的miR164表达降低，从而揭示了缺磷胁迫下侧根形成与miR164调节NAC1表达之间的关系。

Abstract:This study investigated the relationship between the development of tomato lateral roots and auxin, NAC1 (transcription factor involved in the auxin signal transduction) and miR164 expression under P deficiency. Effects of exogenous auxin NAA (1-naphthalene acetic acid) and its transport inhibitor NPA (N-1-naphthylphthalamic acid) on the lateral root development were analyzed under P deficiency (5 μmol/L Pi) versus the control (500 μmol/L Pi). The time course of the expression pattern of miR164 and its target gene, NAC1, were analyzed by RT-PCR. The results showed that the development of lateral roots was promoted by NAA and blocked by NPA. During 12 h of lateral root initiation, expression of NAC1 was strongly up-regulated, while miR164 was down-regulated in P-deficient plants. Our data suggest that miR164, together with its target (NAC1), is involved in the mediation of P-deficiency-induced lateral root development.

---