While red blood cells are carried away at high velocity by a strong blood flow 当红细胞被血流带动,并以高速前进时
leukocytes roll slowly on endothelium cells 白细胞在血管内皮细胞上缓慢滚动
P-selectin on endothelium cells interact with PSGL-1 内皮细胞上的P-选择蛋白与PSGL-1
a glycoprotein on leukocyte microvilli. Leukocytes pushed by the blood flow ——一种白细胞上的糖蛋白相结合 白细胞之所以能
dhere and roll on endothelial cells because the existing interactions are broken 在血管壁的内皮细胞上滚动,就是因为这种结合的不断破坏
while new ones are formed. These interactions are possible 与重建。为这种交互式的结合提供了可能
because the standard extracellular domains of both proteins 是细胞间质隐没的两种蛋白的标准的胞外结构域
immerge from the extracellular matrix, which covers the surfers of both cell types 的标准的胞外结构域,这种细胞间质存在于各种细胞之间
The outer leaflet of the lipid bilayer is rich in single lipids 磷脂双分子层的外叶含有丰富的鞘磷脂
and phosphotidylcholine. Single lipid rich raft 和磷脂胆碱。鞘磷脂组成的脂筏
raised about the rest of the rafts recuse specified membrane proteins. 可以在其周围募集一些特定的膜蛋白。
Rafts rigidity caused by the tight parking of cholesterol molecules 脂筏的刚性有赖于附着在鞘磷脂的
against the straight single lipid hydrocarbon chain. 直链周围的胆固醇分子
Outside the raft,kinks unsaturated chains 脂筏以外,不饱和烃链的纠缠
and lower cholesterol concentration result in increase fluidity. 以及较低的胆固醇浓度导致了流动性的增加。
At sights of information,secreted chemokines 一察觉到信息,由内皮细胞分泌
bind to heparan sulfate proteoglycan endothelial cells 并与硫酸乙酰肝素蛋白多糖（HSPG）结合的趋化激素
endothelial cells are presented to leukocyte's seven transmembrane receptors 就被呈递给白细胞的由7个跨膜区构成的受体
the binding stimulates leukocytes and triggers in 这种粘附刺激白细胞并引发了
intracellular cascade of signaling reactions. The inner leaflet 细胞内的级联通讯反应？？磷脂双分子层的内叶
of the bilayer has very different composition than that of the outer leaflet. 在构成上与外叶有很大不同
while some proteins traverse the membrane, other are either 一些蛋白质横贯质膜,其它则
anchored into the inner leaflet by covalently attach fatty acid chains 通过共价连接脂肪酸
or a recruited through non-covalent interactions 或一个与膜蛋白的非共价作用将
with membrane proteins. The membrane-bound protein complexes 自己锚定在内叶上。膜与蛋白的联合体
are critical for the transmition of signal across the plasma membrane. 是跨膜信号传递中至关重要的部分
The leafy lipid bilayer,spectrin tetramers 在叶状的磷脂双分子层上,血影蛋白
arranged into hexagonal network that are anchored by membrane proteins 被构建成六边形的网状结构,并被膜蛋白锚定。
this network forms the membrane skeleton that contributes to membrane stability 这种网状结构组成了细胞膜的骨架,增强了细胞膜的稳定性
and membrane protein distribution. the cytoskeleton is comprised of networks of 对膜蛋白的分布也有重要作用 细胞骨架由网状结构
filamentous proteins 由微丝蛋白构成
that are responsible for the special organization of cytosoltic 些蛋白质是细胞中特殊组织形成的
components 原因
Inside the microvilli,actin filaments form type 在细胞的微绒毛的内部,肌动蛋白的丝状结
parallel bundles which are stabilized cross-linking proteins 构成了平行的束状纤维,并由横向穿插的蛋白纤维加固
While deeper in the cytosome,the actin networks adapt jawlike structure 在细胞质的更深层,肌动蛋白的网络改变成Z字型的结构
stabilized by a variety of actin binding proteins 并被多种微丝结合蛋白加固
Filaments kep their minus-ends by protein complex, 微丝依靠原肌球调节蛋白蛋稳定其负端
grow away from plasma membrane by the addition of actin polymers 并通过在其正端添加肌动蛋白聚合体向远离质膜的方向
to the plus-end 生长
The actin network is a very dynamic structure 肌动蛋白的网络是一个动态的结构
continuous directional polymerization and disassembly. 持续不断地进行定向的聚合和解聚
severing proteins induce kinks in the filaments and led to the formation of short 裂解蛋白可以引起微丝的断裂而形成较短小的
filaments 微丝
that rapidly depolymerize or give rise to new filaments. 并迅速解聚或者再聚合成新的微丝
The cytososkeleton includes a network microtubules created by the Liberal 细胞骨架还包括微管蛋白构成的网络,这种网络由（13条）微管蛋白原纤维体横向联结构成
Association 联结构成
grew filaments formed with the polymerization tubulin dimers 原纤维则由微管蛋白二聚体头尾相接而成
while the plus-ends of some microtubule extend toward the plasma membrane, 当某些微管的正端向质膜的方向延伸时
protein stabilizes the cure conformation of protofilaments 蛋白质在其它微管上保持着
from other microtubules,causing the rapidly plus-end depolymeriztion. 各种构象间的平衡,使得它们的正端快速解聚
microtubules provide tracts along which membrane bounded vesicles travel to and 微管为运往质膜或来自质膜的由膜结构包裹着的运输泡
from the plasma membrane
with directional movement 提供运输线路
sparkle vesicles is due to a family of motor proteins 这些运输泡的方向性移动应归功于一种与运输泡连接的动力蛋白
linking vesicles and microtubules 组合和微管
membrane-bound organelles like mitochondria are loosely trapped 线粒体一类的膜结构细胞器,由细胞骨架宽松地限制着。
by the cytoskeleton
mitochondria change shape continuously and their orientation is partly 线粒体不断地改变着它们的外型,并靠其与微管的相互作用
dicty by their interaction with microtubules. 部分地改变其方位
over microtubules originate from sensors disagree 所有的微管都发源于中心体
fibrous structures containing 21 model centrioles 中心体包含有一对分开的具有纤维结构的中心粒,
himself
fours in the nuclear envelope allow the importance of articles containing 位于细胞核的附近 核膜上的核孔允许少量的
mRNA and proteins into the cytosol 信使RNA和某些蛋白质进入细胞质
here free ribosomes translate the mRNA moleculesf these proteins will resign from the side to side 这里,游离核糖体#将信使RNA翻译为蛋白质分子,这里制造的蛋白质分子,一些将留在细胞质中
others will associate with specialized cytosolic proteins 其它的将与特异的细胞质结合蛋白相结合
and be imported into what your country a moreover organs
the synthesis cells secreted and integral membrane proteins 而被引入线粒体和其它细胞器
is initiated by free ribosomes which then got to protein translocase 分泌蛋白和膜内在蛋白质的合成开始于游离的核糖体
at the surface of the endoplasmic reticulum nascent proteins pass through 随后将停泊在内质网表面的转运蛋白上继续前行
dicty by their interaction with microtubules 这些蛋白质将通过一个在转运蛋白上的水合的孔
Cell secreted proteins accumulate in the lumen 细胞分泌蛋白
of endoplasmic reticulum while integral membrane proteins become embedded 在内质网的内腔中聚积,而膜内在蛋白质将被植入
in the endoplasmic reticulum membrane 到内质网的膜上
Proteins are transport from the endoplasmic reticulum 将蛋白质从内质网
to the Golgi apparatus(GA) by vesicles travelling along the microtubules 运输到高尔基体,是由沿着微管运动的运输囊泡实现的
Protein glycosylation initiated in the 开始于内质网中的蛋白质糖基化
endplasmic reticulum 在高尔基体中全部完成
is completed inside the lumen of Golgi apparatus. 被植入到内质网的膜上
Fully glycosylated proteins are transported from the Golgi apparatus 完全糖基化的蛋白质分子,将从高尔基体
to the plasma membrane 运送到质膜
When the vesicle fuses with plasma membrane,proteins containing in the vesicle 当运输泡与质膜结合时,在运输泡内腔中的蛋白质将被分泌
lumem
are secreted and proteins embedded in the vesicle membrane 而植入到膜上的蛋白质分子将
diffuse in the cell membrane. At sights of information,chemokine secreted 扩散到细胞膜上。一察觉到信息,趋化激素
by the
endothelial cells bind to the extracellular domains 由内皮细胞分泌的,就与细胞外的G
of G-protein coupled membrane receptors. 蛋白的跨膜受体结构域结合
This binding causes a conformational change in the cytosonic portion of the receptor, 这一结合引起了G-蛋白受体构象上的改变
and consequential activation of the subunit of the G-protein. 而激活了G蛋白的亚基
The activation of the G-protein subunit triggers a cascade of protein activation G蛋白亚基的激活将引发一个蛋白质的级联反应
which in turn leads to the activation and plasterin of 最终将按顺序导致整联蛋白的活化和其在脂筏上
integrin inside lipid rafts. A dramatic conformational change occurs in the 的黏着。一个梯度构象变化发生在
extracellular domain 胞外已活化的
of activated integrins.These now allow for they interaction 整合蛋白的一个区域上。现在整合蛋白可以与
with I-cam proteins display in the surface of the endothelial cells. 内皮细胞表面的I-cam相作用
These strong interactions immobilizethe rolling leukocytes 这种强烈的相互作用使滚动着的白细胞在
at sight of information. Additional signaling events cause profound 察觉到信息时停了下来。附加的信息引起
reorganization of the cytoskeleton, 细胞骨架的大规模改组
resulting in the spreading of one edge of the leukocyte.The leading edge of the 使得白细胞的一个边缘扩散而形成了刀锋状。。白细胞的锋状边缘将
leukocyte inserts itself between 自己插入到内皮细胞的
the endothelial cells, and leukocytes migrate through the blood vessel 孔隙中,白细胞便穿越了血管壁
walls into the inflamed tissue .Rolling, 而进入发炎的组织。滚动、
activation,adhesion,and trans endothelial migration 激活、 附着和穿过内皮细胞是一个过程的四个步骤
are the four steps of a proeess called leukocyte extradrivation. 这个过程被称作白细胞的应激反应