Trad C H, Lipson E D
Department of Physics, Syracuse University, New York 13244-1130.
Biochem Genet. 1989 Jun;27(5-6):355-65. doi: 10.1007/BF00554170.
Certain phototropism mutants of Phycomyces blakesleeanus show defective bending responses (tropisms) to stimuli besides light, such as gravity, wind, and barriers. These so-called "stiff" mutants are affected in four genes (madD to madG). Using two-dimensional gel electrophoresis, we have analyzed polypeptides from microsomal and soluble fractions obtained from the wild type, four single mutants, and six double mutants affected in all pairwise combinations of the four genes. Consistent differences in spot patterns for madE and madF mutants were found in microsomal fractions but not in soluble fractions. In madE mutants, two spots designated E1 (52 kDa, pI 6.65) and E2 (50 kDa, pI 6.65) were altered. E1 appeared denser in the wild type than in the madE mutants, while the reverse was true for E2. The spots E1 and E2 are probably under regulatory control by madE, perhaps involving posttranslational modification. A protein spot, F1 (53 kDa, pI 6.1), was present on the wild-type gels but absent from all gels for madF mutants. The F1 polypeptide probably represents the madF gene product.
布氏毛霉的某些向光性突变体除了对光之外，对重力、风及障碍物等刺激的弯曲反应（向性）存在缺陷。这些所谓的“僵硬”突变体在四个基因（madD至madG）中受到影响。我们利用二维凝胶电泳，分析了从野生型、四个单突变体以及六个双突变体（这六个双突变体在四个基因的所有两两组合中均受影响）获得的微粒体和可溶部分的多肽。在微粒体部分发现了madE和madF突变体在斑点模式上存在一致差异，但在可溶部分未发现。在madE突变体中，两个命名为E1（52 kDa，pI 6.65）和E2（50 kDa，pI 6.65）的斑点发生了改变。E1在野生型中比在madE突变体中显得更密集，而E2则相反。斑点E1和E2可能受madE的调控，或许涉及翻译后修饰。一个蛋白质斑点F1（53 kDa，pI 6.1）出现在野生型凝胶上，但在所有madF突变体的凝胶上均未出现。F1多肽可能代表madF基因产物。
