LISST

这项研究计划的目标是了解结构基础 对于糖酵解酶共定位和靶向Z盘和M盘， 肌节的线条作为一种手段来理解这一重要的 糖酵解酶组织方面为肌肉提供能量 收缩。 在果蝇的飞行肌中， 酶，甘油-3-磷酸脱氢酶（GPDH），甘油醛-3- 磷酸脱氢酶（GAPDH）和醛缩酶位于Z盘/M- 线 GAPDH和醛缩酶的定位依赖于同时的 GPDH的定位。 在没有糖酵解酶的情况下， 在飞行肌肉中的定位，苍蝇不能飞。进一步阐明 支持共定位的蛋白质-蛋白质相互作用的性质 将有助于更好地理解ATP 糖酵解的产物支持肌肉功能。 还有待 确定糖酵解酶是否发生物理相互作用或是否 其它蛋白质在共定位中起作用。 这将是决定 利用酵母双杂交系统和免疫共沉淀技术。 在肌肉特异性同种型中发现的C-末端三肽，Q-N，L， GPDH-1是GPDH靶向所必需的。糖酵解的其他结构域 酶可能在将这些酶靶向Z盘/M盘中起作用。 线，并将被识别。 编码蛋白质的基因 与GPDH和醛缩酶，并在肌肉功能中起重要作用 将通过选择第二位点抑制突变来鉴定。 导致共定位的发育组装过程 糖酵解酶将被表征。 针对其他 糖酵解酶将被研究，其中之一，醛缩酶，将被 广泛发展。 这将需要隔离和表型 醛缩酶基因突变体的表征。 C的作用- 在醛缩酶肌肉特异性同种型中的末端将通过 分析携带工程转基因的转基因果蝇的飞行。 最后，组装过程的细节将以 使用分离的肌原纤维的体外测定的进一步发展 作为一个平台来分析 糖酵解复合物在Z盘/M线处组装和组织。 的 我们的工作成果将对理解 碳水化合物催化剂、能量产生和肌肉之间的联系 功能 这些影响可能会超出 果蝇模型，并应相关的理解缺陷， 人体肌肉功能

This research program has as its goal understanding the structural basis for glycolytic enzyme co-localization and targeting at Z-discs and M- lines of the sarcomere as a means of understanding how this essential aspect of glycolytic enzyme organization provides the energy for muscle contraction. In the flight muscle of Drosophila, the glycolytic enzymes, glycerol-3-phosphate dehydrogenase (GPDH), glyceraldehyde-3- phosphate dehydrogenase (GAPDH) and aldolase are localized at Z-discs/M- lines. Localization of GAPDH and aldolase depends on the simultaneous localization of GPDH. In the absence of glycolytic enzyme co- localization in flight muscles, flies can't fly. Further elucidation of the nature of protein-protein interactions that support colocalization will lead to a better understanding of the mechanisms by which ATP production from glycolysis supports muscle function. It remains to be determined whether glycolytic enzymes physically interact or whether other proteins play a role in co-localization. This will be determined using the yeast two hybrid system and co-immunoprecipitation techniques. The C-terminal tripeptide, Q-N, L found in the muscle specific isoform, GPDH-1 is required for GPDH targeting. Other domains of the glycolytic enzymes may play a role in targeting these enzymes to the Z-discs/M- lines and will be identified. Genes which encode proteins that interact with GPDH and aldolase and are functionally important in muscle function will be identified by selection of second site suppressor mutations. The developmental assembly process that results in co-localized glycolytic enzymes will be characterized. Targeting of additional glycolytic enzymes will be studied and one of these, aldolase, will be extensively developed. This will require isolation and phenotypic characterization of mutants in the aldolase gene. The role of the C- terminus in the aldolase muscle specific isoform will be evaluated by analyzing flight in transgenic flies which carry engineered transgenes. Finally, the details of the assembly process will be characterized by further development of an in vitro assay which uses isolated myofibrils as a platform on which to analyze the mechanism through which the glycolytic complex is assembled and organized at the Z-disc/M-line. The results of our work will have broad implications for understanding the connection between carbohydrate catabolism, energy production and muscle function. It is likely these implications will extend beyond the Drosophila model and should be relevant to understanding defects in human muscle function.