Roles of extensins in cotyledon primordium formation and shoot apical meristem activity in Nicotiana tabacum.
Roles of extensins in cotyledon primordium formation and shoot apical meristem activity in Nicotiana tabacum.
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延伸蛋白在烟草子叶原基形成和芽顶端分生组织活性中的作用。
DOI：
10.1093/jxb/ern245
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发表时间：
2008
影响因子：
6.9
通讯作者：
Zhao J
中科院分区：
文献类型：
--
作者：
Zhang X;Ren Y;Zhao J
伸展蛋白是细胞壁碱性糖蛋白，其多肽骨架富含羟基脯氨酸。本文研究了伸展蛋白在烟草胚发育中的作用。Western blot和免疫组化分析发现，扩展蛋白JIM20表位在胚胎的不同发育阶段均有表达，其中以胚体顶端（EP）和晚期球形胚的胚柄表达最为明显。为了明确伸展蛋白的功能，在胚珠和胚培养中使用了一种有效的羟脯氨酸合成抑制剂3,4-脱氢- l -脯氨酸（3,4- dhp）。结果表明，添加3,4- dhp可导致胚发育异常，子叶原基单一、不对称、多生，连续培养可导致萌发苗子叶缺陷。组织学切片显示，异常苗的茎尖分生组织（SAM）与对照不同，尤其是杯状子叶的幼苗。此外，异常子叶的脉管系统紊乱，至少包含两条主脉。最后，羟脯氨酸实验和荧光免疫定位证实，3,4- dhp处理降低了培养的胚珠和胚胎中延伸蛋白的水平。这些结果表明，伸展蛋白可能在胚发育过程中子叶原基形成、SAM活性和脉管系统分化中起重要作用。
Extensins are cell wall basic glycoproteins with a polypeptide backbone that is extremely rich in hydroxyproline. In this paper, the function of extensins in embryo development was studied in Nicotiana tabacum. By using Western blot and immunohistochemistry, the extensin JIM20 epitopes were found to express in different developmental stages of embryos, and specifically in the top of the embryo proper (EP) and the suspensor of the late globular embryos. In order to clarify the functions of extensins, a potent hydroxyproline synthesis inhibitor, 3,4-dehydro-L-proline (3,4-DHP), was used in ovule and embryo culture. The results showed that the addition of 3,4-DHP caused abnormal embryos with single, asymmetry and supernumerary cotyledon primordia, and continuous culture led to cotyledon defects in the germinated seedlings. Histological sections showed that the shoot apical meristem (SAM) of the abnormal seedlings was dissimilar from the controls, especially in the seedlings with cup-shaped cotyledons. Furthermore, the vasculature of the abnormal cotyledons was in an out-of-order format and contained at least two main veins. Finally, both the hydroxyproline assay and fluorescent immunolocalization confirmed that 3,4-DHP treatment reduced the level of extensins in the cultured ovules and embryos. These results indicate that extensins may play important roles in the cotyledon primordium formation, SAM activity, and vasculature differentiation during embryo development.
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影响因子：
5.1
作者：
Ito, M;Kodama, H;Watanabe, A
通讯作者：
Watanabe, A
影响因子：
64.8
作者：
Blilou, I;Xu, J;Scheres, B
通讯作者：
Scheres, B
影响因子：
7.2
作者：
Hancock, CN;Kent, L;McClure, BA
通讯作者：
McClure, BA
DOI：
10.1073/pnas.0711980105
发表时间：
2008-02-12
影响因子：
11.1
作者：
Cannon, Maura C.;Terneus, Kimberly;Kieliszewski, Marcia J.
通讯作者：
Kieliszewski, Marcia J.
影响因子：
11.6
作者：
Ahn, JH;Choi, Y;Lee, JS
通讯作者：
Lee, JS