Schreckenbach T, Verfuerth C
Eur J Cell Biol. 1982 Aug;28(1):12-26.
The differentiation of starving Physarum polycephalum microplasmodia into resting structures (spherules) was studied. Early events in this differentiation pathway include decreases in both plasmodial motility and protein synthesis. The starving plasmodia show a blue light avoidance response. Blue light (lambda max 450 nm, irradiance 16 W/m2) acts antagonistically to the starvation stimulus so that spherule formation is inhibited [16]. Light affects each of the above mentioned events of the differentiation pathway: the migration rate of illuminated plasmodia is stimulated, the light avoidance response is irreversibly lost. The rate of incorporation of radioactive leucine into plasmodial protein remains at a higher level in illuminated plasmodia as compared to the decreasing rate during spherule formation in the dark. Protein degradation, uptake of external leucine, and the size of the internal leucine pool are not affected by light. Analysis by SDS-polyacrylamide gel electrophoresis of pulse-labelled plasmodial proteins reveals that blue light inhibits the synthesis of distinct starvation-induced proteins and allows continued synthesis of all major plasmodial proteins. Some of the blue light responses described are mimicked by alpha-amanitin suggesting that light might influence gene expression at the level of transcription.
对饥饿的多头绒泡菌微原质团分化为静止结构（球形体）的过程进行了研究。该分化途径中的早期事件包括原质团运动性和蛋白质合成的降低。饥饿的原质团表现出蓝光回避反应。蓝光（最大波长450nm，辐照度16W/m²）对饥饿刺激起拮抗作用，从而抑制球形体的形成[16]。光影响上述分化途径中的每一个事件：光照下原质团的迁移速率受到刺激，蓝光回避反应不可逆地丧失。与黑暗中球形体形成过程中放射性亮氨酸掺入原质团蛋白质的速率下降相比，光照下原质团中该速率保持在较高水平。蛋白质降解、外部亮氨酸的摄取以及内部亮氨酸池的大小不受光的影响。对脉冲标记的原质团蛋白质进行SDS-聚丙烯酰胺凝胶电泳分析表明，蓝光抑制了特定饥饿诱导蛋白的合成，并允许所有主要原质团蛋白质继续合成。所描述的一些蓝光反应被α-鹅膏蕈碱模拟，这表明光可能在转录水平上影响基因表达。
