Nup120p: A yeast nucleoporin required for NPC distribution and mRNA transport
Nup120p: A yeast nucleoporin required for NPC distribution and mRNA transport
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DOI：
10.1083/jcb.131.6.1659
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发表时间：
1995-12-01
影响因子：
7.8
通讯作者：
Rout, MP
中科院分区：
文献类型：
--
作者：
Aitchison, JD;Blobel, G;Rout, MP
为了扩大我们对核孔复合物（NPC）介导核膜大分子运输的机制的理解，我们重点研究了酵母NPC的组成和分子组织。对高富集酵母NPC片段中M(r)接近10万的多肽进行多肽序列分析，鉴定出一种新的酵母核孔蛋白Nup120p。Nup120p与酵母基因组测序项目鉴定的开放阅读框（ORF） YKL057c相对应。ORF预测了一个计算分子质量为120.5 kD的蛋白质，包含两个亮氨酸拉链基序，一个短卷曲线圈区域和有限的初级序列与Nup133p相似。通过间接免疫荧光显微镜，利用蛋白a标记嵌合体原位定位Nup120p。NUP120基因的缺失导致核膜一侧的npc聚集，核仁中度断裂，细胞生长减慢。将nup120 Delta细胞转移到37℃，导致细胞核聚积poly(A)(+) mRNA，核仁大面积断裂，纺锤体缺陷和细胞死亡。
To extend our understanding of the mechanism by which the nuclear pore complex (NPC) mediates macromolecular transport across the nuclear envelope we have focused on defining the composition and molecular organization of the yeast NPC. Peptide sequence analysis of a polypeptide with a M(r) of similar to 100,000 present in a highly enriched yeast NPC fraction identified a novel yeast nucleoporin we term Nup120p. Nup120p corresponds to the open reading frame (ORF) YKL057c identified by the yeast genome sequencing project. The ORF predicts a protein with a calculated molecular mass of 120.5 kD containing two leucine zipper motifs, a short coiled-coil region and limited primary sequence similarity to Nup133p. Nup120p was localized to the NPC using a protein A-tagged chimera in situ by indirect immunofluorescence microscopy. Deletion of the NUP120 gene caused clustering of NPCs at one side of the nuclear envelope, moderate nucleolar fragmentation and slower cell growth. Transfer of nup120 Delta cells to 37 degrees C resulted in the nuclear accumulation of poly(A)(+) mRNA, extensive fragmentation of the nucleolus, spindle defects, and cell death.