An analysis of the blue light mediated increase of protein synthesis in fern gametophytes on the level of amino acids

Abstract
Morphogenesis and metabolism of the sporelings (= young gametophytes) of the common male fern Dryopteris filix-max are controlled by visible radiation. Short wavelengths visible radiation (= blue light) leads to an increase in protein synthesis and makes possible the formation of “normal” two-dimensional prothallia. Under long wavelengths visible radiation (= red light) the sporelings grow as cellular filaments, the protein contents of which are markedly lower than under blue light even under conditions of equal rate of dry matter accumulation in red and blue light (Fig. 2). — Quantitative amino acid analysis of the total protein of blue and red grown sporelings did not reveal any striking difference. The contents of all those amino acids which can be measured quantitatively after protein hydrolysis show about the same increase under the influence of blue light (Figs. 3, 4). Only in the case of proline are the differences between red grown and blue grown sporelings indicative of a qualitative change in the nature of the protein fraction (Fig. 3/h). —The pools of the free amino acids are always smaller in blue grown sporelings than in red grown ones (Figs. 6, 7). — The facts reported in this paper indicate that blue light leads mainly to a quantitative increase in the rate of protein synthesis. The influence of blue light on the qualitative nature of the protein fraction seems to be slight. On the other hand, the data on the pool sizes of the free amino acids support the conclusion that blue light controls the rate of protein synthesis at the stage of polypeptide synthesis and not through amino acid synthesis. Bei der quantitativen Analyse der Protein-Aminosäuren von Farnvorkeimen (Dryopteris filix-mas) ergab sich, daß die Steigerung des Proteingehalts durch Blaulicht mit einer Zunahme aller untersuchten Aminosäuren einhergeht. Dabei bleibt der prozentuale Anteil der einzelnen Aminosäuren am Gesamtprotein immer annähernd gleich, abgesehen vom Prolin. — Offenbar kommt es unter dem Einfluß von Blaulicht hauptsächlich zu einer quantitativen Vermehrung und nur im geringen Maße zu einer qualitativen Veränderung der Proteinfraktion. — Da die pools der erfaßbaren freien Aminosäuren im Hellrot stets größer sind als im Blaulicht, ist der Schluß berechtigt, daß das Blaulicht seine Wirkung im Zusammenhang mit der Polypeptidsynthese und nicht über eine Steigerung der Aminosäuresynthese ausübt.