Expresses of MiARF2, an auxin response factor like gene isolated from mango (Mangifera indica L.), and adventitious root development

【作者】 陈启助； 李运合； 吴蓓； 黄霞； 陈云凤； 李筱菊； 黄学林；

【Author】 Qi-Zhu Chena, Yun-He Lib, Bei Wua, Xia Huanga, Yun-Feng Chena, Xiao-Ju Li a,X ue-Lin Huang a aThe Key Laboratory of Gene Engineering of the Ministry of Education, School of Life Science, Sun Yat-sen (Zhongshan) University, Guangzhou 510275, China bSouth Subtropical Crop Research Institute, Chinese Academy of Tropical Agricultural Science, Zhanjiang 524091, China

【机构】 The Key Laboratory of Gene Engineering of the Ministry of Education,School of Life Science,Sun Yat-sen(Zhongshan) University(中山大学)； South Subtropical Crop Research Institute,Chinese Academy of Tropical Agricultural Science；

【摘要】 In previous study we cloned ARFs-like gene, mango auxin response factor 2 gene (MiARF2) during adventitious roots formation of mango (Mangifera indica L. cv. Zihua) cotyledon sections and found that it share 84% amino acid sequence similarity with the Arabidopsis ARF2 [1] To investigate function of this gene, in this study we examine when and where the MiARF2 is expressed by Real-time RT-PCR and In Situ Hybridization in this system of adventitious root formation, which were only from the proximal cut surface (PCS) of mango cotyledon crosscut segment [2], and observed effect of MiARF2 overexpression on adventitious root formation induced from hypocotyls of Arabidopsis transgenic lines ( 35S: MiARF2). The results showed that expression of MiARF2 was increased in PCS during the root induction for 7 days (at adventitious root initiation stage), and reached to the maximal expression level at 10 days for the roots induction. By contrast, no expression of MiARF2 could be detected in distal cut surface (DCS) during corresponding time in the PCS. In Situ Hybridization of the mRNA also indicated that MiARF2 could be detected only on PCS, and the higher level of the expression was in vascular bundle, especially in epithelial cells and parenchyma cells of phloem outside laticiferous canal, where is cytological original of the root formation. On the other hand, overexpression of MiARF2 increased the adventitious roots length induced from hypocotyls of the Arabidopsis transgenic lines in comparison with the wild-type. These results suggests that although MiARF2 only has a single DNA-binding domain (DBD), it can function as a regulator in adventitious roots formation induced from mango cotyledon segment or from hypocotyls of the Arabidopsis transgenic lines.更多还原

【Abstract】 In previous study we cloned ARFs-like gene, mango auxin response factor 2 gene (MiARF2) during adventitious roots formation of mango (Mangifera indica L. cv. Zihua) cotyledon sections and found that it share 84% amino acid sequence similarity with the Arabidopsis ARF2 [1] To investigate function of this gene, in this study we examine when and where the MiARF2 is expressed by Real-time RT-PCR and In Situ Hybridization in this system of adventitious root formation, which were only from the proximal cut surface (PCS) of mango cotyledon crosscut segment [2], and observed effect of MiARF2 overexpression on adventitious root formation induced from hypocotyls of Arabidopsis transgenic lines ( 35S: MiARF2). The results showed that expression of MiARF2 was increased in PCS during the root induction for 7 days (at adventitious root initiation stage), and reached to the maximal expression level at 10 days for the roots induction. By contrast, no expression of MiARF2 could be detected in distal cut surface (DCS) during corresponding time in the PCS. In Situ Hybridization of the mRNA also indicated that MiARF2 could be detected only on PCS, and the higher level of the expression was in vascular bundle, especially in epithelial cells and parenchyma cells of phloem outside laticiferous canal, where is cytological original of the root formation. On the other hand, overexpression of MiARF2 increased the adventitious roots length induced from hypocotyls of the Arabidopsis transgenic lines in comparison with the wild-type. These results suggests that although MiARF2 only has a single DNA-binding domain (DBD), it can function as a regulator in adventitious roots formation induced from mango cotyledon segment or from hypocotyls of the Arabidopsis transgenic lines.更多还原