TANGO1 membrane helices create a lipid diffusion barrier at curved membranes
TANGO1 membrane helices create a lipid diffusion barrier at curved membranes
复制标题
DOI：
10.7554/elife.57822
复制
发表时间：
2020-05-26
期刊：
影响因子：
7.7
通讯作者：
Malhotra, Vivek
中科院分区：
文献类型：
--
作者：
Raote, Ishier;Ernst, Andreas M.;Malhotra, Vivek
我们先前已经显示TANGO 1在内质网（ER）和ERGIC/高尔基体的界面处组织膜（Raote等人，2018年）。TANGO 1在ER出口部位使皮质逆行膜形成出口管道。逆行膜本身就是顺行载体。这种向前运输的模式需要一种机制来防止ER和逆行膜之间的膜混合。TANGO 1具有不寻常的膜螺旋组织，由一个跨膜螺旋（TM）和另一个穿透内小叶（IM）组成。我们已经重建了这些膜螺旋模型膜，并表明TM和IM一起减少了脂质在一个区域的定义形状的流动。我们还表明，螺旋排列TANGO 1周围的ER出口网站。我们认为，这是一种机制，以防止膜混合在TANGO 1介导的大型分泌货物从ER的ERGIC/高尔基体通过隧道转移。
We have previously shown TANGO1 organises membranes at the interface of the endoplasmic reticulum (ER) and ERGIC/Golgi (Raote et al., 2018). TANGO1 corrals retrograde membranes at ER exit sites to create an export conduit. Here the retrograde membrane is, in itself, an anterograde carrier. This mode of forward transport necessitates a mechanism to prevent membrane mixing between ER and the retrograde membrane. TANGO1 has an unusual membrane helix organisation, composed of one membrane-spanning helix (TM) and another that penetrates the inner leaflet (IM). We have reconstituted these membrane helices in model membranes and shown that TM and IM together reduce the flow of lipids at a region of defined shape. We have also shown that the helices align TANGO1 around an ER exit site. We suggest this is a mechanism to prevent membrane mixing during TANGO1-mediated transfer of bulky secretory cargos from the ER to the ERGIC/Golgi via a tunnel.