An invertase inhibitor from maize localizes to the embryo surrounding region during early kernel development
An invertase inhibitor from maize localizes to the embryo surrounding region during early kernel development
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DOI：
10.1104/pp.103.027466
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发表时间：
2004-01-01
期刊：
影响因子：
7.4
通讯作者：
Helentjaris, TG
中科院分区：
文献类型：
--
作者：
Bate, NJ;Niu, XP;Helentjaris, TG
转化酶活性被认为在早期籽粒发育过程中发挥调节作用，通过将来源于源叶的蔗糖转化为己糖以支持胚乳和胚中的细胞分裂。转化酶在翻译后水平受小蛋白抑制剂INVINH的调节。我们发现，在玉米（玉米），转化酶抑制剂同源物（ZM-INVINH 1）的表达早在籽粒发育，授粉后4和7天之间。在重组ZM-INVINH 1存在下，体外转化酶活性降低，并且通过与蔗糖预孵育减弱抑制。推定的信号肽的存在下，分馏实验，和ZM-INVINH 1：：绿色荧光蛋白融合实验表明，蛋白质输出到质外体。此外，协会的ZM-INVINH 1与糖蛋白级分伴刀豆球蛋白A层析表明，ZM-INVINH 1相互作用与质外体转化酶在早期籽粒发育。通过原位分析，ZM-INVINH 1定位于胚周围区域，表明该区域形成边界，分隔质外体转化酶活性以允许不同的胚和胚乳发育速率。
Invertase activity is thought to play a regulatory role during early kernel development by converting sucrose originating from source leaves into hexoses to support cell division in the endosperm and embryo. Invertases are regulated at the posttranslational level by small protein inhibitors, INVINHs. We found that in maize (Zea mays), an invertase inhibitor homolog (ZM-INVINH1) is expressed early in kernel development, between 4 and 7 d after pollination. Invertase activity is reduced in vitro in the presence of recombinant ZM-INVINH1, and inhibition is attenuated by pre-incubation with sucrose. The presence of a putative signal peptide, fractionation experiments, and ZM-INVINH1::green fluorescent protein fusion experiments indicate that the protein is exported to the apoplast. Moreover, association of ZM-INVINH1 with the glycoprotein fraction by concanavalin A chromatogaphy suggests that ZM-INVINH1 interacts with an apoplastic invertase during early kernel development. ZM-INVINH1 was localized to the embryo surrounding region by in situ analysis, suggesting that this region forms a boundary, compartmentalizing apoplast invertase activity to allow different embryo and endosperm developmental rates.