Cahill A, Baio D L, Cunningham C C
Department of Biochemistry, Wake Forest University Medical Center, Winston Salem, North Carolina 27157, USA.
Anal Biochem. 1995 Nov 20;232(1):47-55. doi: 10.1006/abio.1995.9962.
A procedure has been developed that allows characterization of mitochondrial ribosomes and quantitative analysis of the relative composition of constitutive ribosomal proteins. Purified mitochondrial ribosomes were isolated from two rat livers and shown to be active in catalyzing the polymerization of phenylalanine. They differ in sedimentation and spectral properties from cytoplasmic ribosomes isolated from the same livers. The number and relative composition of proteins present in active rat liver mitochondrial ribosomes were investigated using two-dimensional nonequilibrium pH gradient electrophoresis. There were 86 proteins found associated with mitochondrial ribosomes in contrast to 70 proteins found associated with cytoplasmic ribosomes. Comparison of electrophoretic patterns revealed that cytoplasmic ribosomal proteins were considerably more basic than their mitochondrial counterparts. Densitometry demonstrated that the relative changes in the concentrations of these proteins can be measured quantitatively. These procedures, developed for use with two rat livers, allow the rat to be used as an efficient model for further studies into disease states of mitochondrial translation.
已开发出一种方法，可用于表征线粒体核糖体并对组成型核糖体蛋白的相对组成进行定量分析。从两只大鼠肝脏中分离出纯化的线粒体核糖体，并证明其在催化苯丙氨酸聚合反应中具有活性。它们在沉降和光谱特性方面与从同一肝脏中分离出的细胞质核糖体不同。使用二维非平衡pH梯度电泳研究了活性大鼠肝脏线粒体核糖体中存在的蛋白质数量和相对组成。发现与线粒体核糖体相关的蛋白质有86种，而与细胞质核糖体相关的蛋白质有70种。电泳图谱比较显示，细胞质核糖体蛋白比线粒体对应蛋白的碱性要强得多。密度测定法表明，可以定量测量这些蛋白质浓度的相对变化。这些针对两只大鼠肝脏开发的方法，使大鼠能够作为进一步研究线粒体翻译疾病状态的有效模型。
