Matsumoto S, Ogawa M, Kasakura T, Shimada Y, Mitsui M, Maruya M, Isohata M, Yahara I, Murakami-Murofushi K
Department of Cell Biology, The Tokyo Metropolitan Institute of Medical Science, Bunkyo-ku, Tokyo, 113-8613, Japan.
J Biochem. 1998 Aug;124(2):326-31. doi: 10.1093/oxfordjournals.jbchem.a022115.
When exposed to various stresses including heat shock, myxoamoebae, growing haploid cells of Physarum polycephalum, show marked morphological changes and consequently become disk-shaped microcysts. We have found that p66 is induced exclusively in the course of microcyst formation and has an actin-binding activity. In this study, we purified p66 to homogeneity and isolated a p66 cDNA. The deduced protein sequence contained 601 amino acids and showed 31% identity to a yeast actin-interacting protein, AIP1. Northern blot analysis revealed that the amount of p66 mRNA was significantly increased by heat shock in myxoamoebae but not in plasmodia. Thus, p66 seems to be a developmentally-expressed stress protein which regulates the rearrangement of actin organization during microcyst formation in P. polycephalum.
多头绒泡菌的单倍体生长细胞——黏液变形虫，在受到包括热休克在内的各种应激时，会表现出明显的形态变化，并最终变成盘状微囊肿。我们发现，p66仅在微囊肿形成过程中被诱导产生，并且具有肌动蛋白结合活性。在本研究中，我们将p66纯化至同质，并分离出了p66 cDNA。推导的蛋白质序列包含601个氨基酸，与酵母肌动蛋白相互作用蛋白AIP1有31%的同源性。Northern印迹分析表明，热休克可使黏液变形虫中p66 mRNA的量显著增加，但在原质团中则不然。因此，p66似乎是一种在发育过程中表达的应激蛋白，它在多头绒泡菌微囊肿形成过程中调节肌动蛋白组织的重排。
