An auxin‐responsive endogenous peptide regulates root development in Arabidopsis  

作　　者：Fengxi Yang Yu Song Hao Yang Zhibin Liu Genfa Zhu Yi Yang 

机构地区：[1]Key Laboratory of Bio‐Resources and Eco‐Environment of Ministry of Education, College of Life Sciences, Sichuan University [2]Floricultural Research Institute, Guangdong Academy of Agricultural Sciences [3]Center for Integrative Conservation, Xishuangbanna Tropical Botanical Garden, the Chinese Academy of Sciences [4]Graduate School of the Chinese Academy of Sciences

出　　处：《Journal of Integrative Plant Biology》2014年第7期635-647,共13页植物学报（英文版）

基　　金：funded by the National Natural Science Foundation of China(30971557,30971816,and31300996);the Guangdong Natural Science Foundation(S2011010001433)

摘　　要：Auxin plays critical roles in root formation and development. The components involved in this process, however, are not well understood. Here, we newly identified a peptide encoding gene, auxin-responsive endogenous polypeptide 1 （AREP1）, which is induced by auxin, and mediates root development in Arabidopsis. Expression of AREP1 was specific to the cotyledon and to root and shoot meristem tissues. Amounts of AREP1 transcripts and AREP1-green fluorescent protein fusion proteins were elevated in response to indoleacetic acid treatment. Suppression of AREP1 through RNAi silencing resulted in reduction of primary root length, increase of lateral root number, and expansion of adventitious roots, compared to the observations in wild-type plants in the presence of auxin. By contrast, transgenic plants overexpressing AREP1 showed enhanced growth of the primary root under auxin treatment. Additionally, rootmorphology, including lateral root number and adventitious roots, differed greatly between transgenic and wildtype plants. Further analysis indicated that the expression of auxin-responsive genes, such as IAA3, IAA7, IAA17, GH3.2, GH3.3, and SAUR-AC1, was significantly higher in AREP1 RNAi plants, and was slightly lower in AREP1 overexpressing plants than in wildtype plants. These results suggest that the novel endogenous peptide AREP1 plays an important role in the process of auxinmediated root development.Auxin plays critical roles in root formation and development. The components involved in this process, however, are not well understood. Here, we newly identified a peptide encoding gene, auxin-responsive endogenous polypeptide 1 （AREP1）, which is induced by auxin, and mediates root development in Arabidopsis. Expression of AREP1 was specific to the cotyledon and to root and shoot meristem tissues. Amounts of AREP1 transcripts and AREP1-green fluorescent protein fusion proteins were elevated in response to indoleacetic acid treatment. Suppression of AREP1 through RNAi silencing resulted in reduction of primary root length, increase of lateral root number, and expansion of adventitious roots, compared to the observations in wild-type plants in the presence of auxin. By contrast, transgenic plants overexpressing AREP1 showed enhanced growth of the primary root under auxin treatment. Additionally, rootmorphology, including lateral root number and adventitious roots, differed greatly between transgenic and wildtype plants. Further analysis indicated that the expression of auxin-responsive genes, such as IAA3, IAA7, IAA17, GH3.2, GH3.3, and SAUR-AC1, was significantly higher in AREP1 RNAi plants, and was slightly lower in AREP1 overexpressing plants than in wildtype plants. These results suggest that the novel endogenous peptide AREP1 plays an important role in the process of auxinmediated root development.

关 键 词：Auxin response endogenous peptide root developmentCitation： Yang F  Song Y  Yang H  Liu Z  Zhu G  Yang Y （2014） An auxin-responsive endogenous peptide regulates root development in 

分 类 号：Q946[生物学—植物学]