LOCALIZATION OF THE GOLGI COMPLEX

细胞生物学中的一个基本问题是细胞器如何实现其 明显的细胞质定位。在间期细胞中，高尔基体 复合体位于微管组织中心附近。 (MTOC)，在核包膜的一侧。在有丝分裂期间，高尔基体 囊泡形成较小的单位，分散在细胞质中。 在末期，小泡结合并返回到中央周围。 地点。这项研究的长期目标是阐明 负责特定和细胞周期的蛋白质-蛋白质相互作用- 高尔基复合体受调控的亚细胞定位。我们已经展示了 孤立的高尔基复合体可以与细胞质成分相互作用 半完整的细胞，并聚集在中心体附近。 这一过程需要ATP的水解，存在完好无损 微管，并完全依赖于基于微管的马达， 胞质动力蛋白。本提案的具体目标是 分离和表征我们已经展示的一个潜在的新因素 对于高尔基体在中心体的积累是必不可少的。这一因素可以 通过KCI处理，从高尔基体膜中释放。我们希望确定 如果这种蛋白质作为连接物将高尔基复合体与动力蛋白偶联， 和/或微管，以细胞周期调节的方式。这一因素具有 可能代表一类新的蛋白质，这些蛋白质可以连接一个 分子马达连接到特定的膜结合细胞器。

A fundamental question in cell biology is how organelles achieve their distinct cytoplasmic localizations. In interphase cells, the Golgi complex is found in close proximity to the microtubule-organizing center (MTOC), on one side of the nuclear envelope. During mitosis, the golgi vesiculates into smaller units which disperse throughout the cytoplasm. At telophase, the vesicles coalesce and return to a pericentriolar location. The long term goal of this research is to elucidate the protein-protein interactions responsible for the specific and cell cycle- regulated, subcellular localization of the Golgi complex. We have shown that isolated Golgi complexes can interact with cytoplasmic components of semi-intact cells, and accumulate in the vicinity of the centrosome. This process requires ATP hydrolysis, the presence of intact microtubules, and is entirely dependent upon the microtubule-based motor, cytoplasmic dynein. The specific aims of the present proposal are to isolate and characterize a potentially novel factor that we have shown is essential for Golgi accumulation at the centrosome. This factor can be released from Golgi membranes by KCI treatment. We wish to determine if this protein acts as a linker to couple the Golgi complex to dynein, and/or microtubules, in a cell-cycle-regulated fashion. This factor has the potential to represent a new class of proteins that can link a molecular motor to a specific membrane-bound organelle.