The sea urchin egg jelly coat consists of globular glycoproteins bound to a fibrous fucan superstructure.
The sea urchin egg jelly coat consists of globular glycoproteins bound to a fibrous fucan superstructure.
复制标题
海胆蛋果冻外壳由与纤维状岩藻聚糖上层结构结合的球状糖蛋白组成。
DOI：
10.1006/dbio.1994.1088
复制
发表时间：
1994
影响因子：
2.7
通讯作者：
Chandler,DE
中科院分区：
文献类型：
--
作者：
Bonnell,BS;Keller,SH;Vacquier,VD;Chandler,DE
完整的卵冻（EJ）外套周围的海胆卵Strongylocentrotus purpuratus可视化立体图像的铂复制品生产的速冻，深蚀刻，旋转阴影技术。水合的EJ外套形成广泛的纤维网络，与卵表面的卵黄层接触。纤维沿着其长度用颗粒装饰，颗粒密度在涂层的内部区域最高。组成EJ网络的大分子组分通过云母吸附的EJ样品的旋转阴影来可视化。整个EJ涂层溶解在pH 5的海水和云母表面上的蔓延组成的复杂网络的分支纤维装饰有大块的无定形材料。正如我们之前所展示的，（Keller和Vacquier，1994），EJ在含有SDS和β-巯基乙醇的溶解缓冲液中煮沸并施加到Sephacryl-500凝胶过滤柱上，可以分离成三个级分：380-kDa岩藻糖硫酸盐聚合物（FSP），其在空隙体积中洗脱，和由中间（300 kDa）和低分子量（30- 138-kDa）糖蛋白组成的两个包含柱的级分。FSP级分的旋转阴影显示分支纤维组分在外观上类似于溶解的整个EJ，但没有任何颗粒装饰。相比之下，中等和低分子量的EJ组件是严格的球形外观，但可区分的基础上的大小。整个EJ的离子交换纯化产生两种糖蛋白，82和138 kDa，具有AR诱导活性（Keller和Vacquier，1994）。铂复制显示这些活性组分是直径约8 nm的小球形分子。上述分馏方案需要苛刻的解离条件。事实上，如果EJ在分级分离之前没有在SDS缓冲液中煮沸，则300-kDa级分和FSP一起出现在空隙体积中。这个复杂的旋转阴影揭示了一个多链聚合物，装饰在特定的扭结点的糖蛋白。两者合计，我们的数据表明，EJ网络是由一个岩藻糖硫酸盐聚合物的超结构，糖蛋白结合。
Intact egg jelly (EJ) coats surrounding eggs of the sea urchinStrongylocentrotus purpuratuswere visualized in stereo images of platinum replicas produced by the quick-freeze, deep-etch, rotary-shadowing technique. The hydrated EJ coat forms an extensive fibrous network that makes contact with the vitelline layer at the egg surface. Fibers are decorated along their length with particles, particle density being highest in the interior regions of the coat. The macromolecular components making up the EJ network were visualized by rotary-shadowing of mica-adsorbed EJ samples. Whole EJ coats solubilized in pH 5 seawater and spread on the mica surface consist of complex networks of branching fibers decorated with large patches of amorphous material. As we have previously shown (Keller and Vacquier, 1994), EJ boiled in a dissolution buffer containing SDS and β-mercaptoethanol and applied to a Sephacryl-500 gel filtration column can be separated into three fractions: a 380-kDa fucose sulfate polymer (FSP), which elutes in the void volume, and two column-included fractions consisting of intermediate (300 kDa) and low-molecular-weight (30- to 138-kDa) glycoproteins. Rotary-shadowing of the FSP fraction reveals branched fibrous components similar in appearance to that of solubilized whole EJ but devoid of any particulate decoration. In contrast, intermediate- and low-molecular-weight EJ components are strictly globular in appearance but are distinguishable on the basis of size. Ion-exchange purification of whole EJ yields two glycoproteins, of 82 and 138 kDa, having AR-inducing activity (Keller and Vacquier, 1994). Platinum replication shows these active components to be small spherical molecules about 8 nm in diameter. The above fractionation scheme requires harsh dissociation conditions. Indeed, if EJ is not boiled in SDS buffer before fractionation, the 300-kDa fraction and the FSP appear together in the void volume. Rotary-shadowing of this complex reveals a multistranded polymer, decorated with glycoproteins at specific kink points. Taken together, our data suggest that the EJ network is composed of a fucose sulfate polymer superstructure to which glycoproteins are bound.