Bassham D C, Raikhel N V
Michigan State University-Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824-1312, USA.
Plant Physiol. 1998 Jun;117(2):407-15. doi: 10.1104/pp.117.2.407.
The Sec1p family of proteins is required for vesicle-mediated protein trafficking between various organelles of the endomembrane system. This family includes Vps45p, which is required for transport to the vacuole in yeast (Saccharomyces cerevisiae). We have isolated a cDNA encoding a VPS45 homolog from Arabidopsis thaliana (AtVPS45). The cDNA is able to complement both the temperature-sensitive growth defect and the vacuolar-targeting defect of a yeast vps45 mutant, indicating that the two proteins are functionally related. AtVPS45p is a peripheral membrane protein that associates with microsomal membranes. Sucrose-density gradient fractionation demonstrated that AtVPS45p co-fractionates with AtELP, a potential vacuolar protein sorting receptor, implying that they may reside on the same membrane populations. These results indicate that AtVPS45p is likely to function in the transport of proteins to the vacuole in plants.
Sec1p蛋白家族是内膜系统中各种细胞器之间囊泡介导的蛋白质运输所必需的。该家族包括Vps45p，它是酵母（酿酒酵母）中运输至液泡所必需的。我们从拟南芥中分离出了一个编码VPS45同源物的cDNA（AtVPS45）。该cDNA能够弥补酵母vps45突变体的温度敏感型生长缺陷和液泡靶向缺陷，表明这两种蛋白质在功能上相关。AtVPS45p是一种与微粒体膜相关的外周膜蛋白。蔗糖密度梯度分级分离表明，AtVPS45p与AtELP（一种潜在的液泡蛋白分选受体）共分级，这意味着它们可能存在于相同的膜群体上。这些结果表明，AtVPS45p可能在植物中蛋白质向液泡的运输中发挥作用。
