Fields S D, Conrad M N, Clarke M
Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA.
J Cell Sci. 1998 Jun;111 ( Pt 12):1717-27. doi: 10.1242/jcs.111.12.1717.
The cluA gene, encoding a novel 150 kDa protein, was recently characterized in Dictyostelium discoideum; disruption of cluA impaired cytokinesis and caused mitochondria to cluster at the cell center. The genome of Saccharomyces cerevisiae contains an open reading frame (CLU1) that encodes a protein that is 27% identical, 50% similar, to this Dictyostelium protein. Deletion of CLU1 from S. cerevisiae did not affect cell viability, growth properties, sporulation efficiency, or frequency of occurrence of cells lacking functional mitochondria. However, in clu1Delta cells the mitochondrial reticulum, which is normally highly branched, was condensed to one side of the cell. Transformation of cluA- Dictyostelium mutants with the yeast CLU1 gene yielded amoebae that divided normally and had dispersed mitochondria. The mitochondria in cluA- Dictyostelium cells complemented with CLU1 were not as widely scattered as in cluA+ Dictyostelium cells, but formed loose clusters throughout the cytoplasm. These results indicate that the products of the CLU1 and cluA genes, in spite of their limited homology, are functional homologues.
最近在盘基网柄菌中鉴定出了编码一种新型150 kDa蛋白的cluA基因；cluA基因的破坏损害了胞质分裂，并导致线粒体聚集在细胞中心。酿酒酵母的基因组包含一个开放阅读框（CLU1），其编码的蛋白与这种盘基网柄菌蛋白有27%的同一性和50%的相似性。从酿酒酵母中删除CLU1并不影响细胞活力、生长特性、孢子形成效率或缺乏功能性线粒体的细胞的出现频率。然而，在clu1Δ细胞中，通常高度分支的线粒体网状结构浓缩到细胞的一侧。用酵母CLU1基因转化cluA -盘基网柄菌突变体产生了能正常分裂且线粒体分散的变形虫。与CLU1互补的cluA -盘基网柄菌细胞中的线粒体不像cluA +盘基网柄菌细胞中的线粒体那样广泛分散，而是在整个细胞质中形成松散的簇。这些结果表明，尽管CLU1和cluA基因的产物同源性有限，但它们是功能同源物。
