Studies on the mechanism of flagellar movement using mammalian seminal plasma motility inhibitor protein.

哺乳动物精浆中含有一种抑制去膜鞭毛运动的物质。该抑制剂(SPMI，精浆动力抑制物)是从公猪中制备的。纯化的SPMI由SDSPAGE中的14、16和18kD三个亚基组成。SPMI不仅抑制哺乳动物的精子鞭毛运动，而且对鱼类和海胆的精子鞭毛运动也有抑制作用，似乎普遍抑制鞭毛运动。当去膜海胆精子鞭毛暴露于SPMI时，弯曲幅度明显降低，随后出现不规则搏动，然后停止。SPMI抑制了双微管的滑行解体，但鞭毛末端分裂成单个微管，弯曲部分松弛。SPMI可部分抑制ATPase活性。推测鞭毛弯曲的幅度与鞭毛轴丝的粘弹性密切相关，SPMI使其增强。还观察到，当SPMI浓度较高时，弯曲扩展非常缓慢。在这种情况下，在弯曲传播过程中保留了一些波形参数，这表明这些参数对于理解鞭毛运动的控制机制非常重要。只有碱性和高分子量(15kD或以上)的多氨基酸如多L赖氨酸(PLL)对鞭毛运动有抑制作用。PLL抑制的是弯曲幅度，而不是拍频。即使在高浓度PLL存在的情况下，弯曲也是松弛的。这些结果表明，PLL在某些部位的抑制方式与SPMI相似。因此，PLL可能增加了微管间的粘弹性。向海胆卵裂球显微注射SPMI。SPMI在细胞分裂前的一段时间内起到一定的抑制作用。

Mammalian seminal plasma contains a inhibitor to immobilize the demembranated flagellar movement. The inhibitor (SPMI, seminal plasma motility inhibitor) was prepared from the boar. The purified SPMI was consisted with three subunits, 14, 16 and 18 KD in SDSPAGE. SPMI inhibited not only mammalian but also fish and sea urchin sperm flagellar movement so that it seemed to inhibit the flagellar movement universally. When the demembranated sea urchin sperm flagella were exposed to SPMI the amplitude of bend decreased apparently, followed by irregular beat and then, stopped. The sliding disintegration of doublet microtubules were inhibited by SPMI, however, the end of flagella split out to individual microtubules and the bends were relaxed. ATPase activity was partially inhibited by SPMI. It was assumed that the amplitude of flagellar bend was closely related to the viscoelasticity in flagellar axoneme and SPMI increased it. It was also observed that the very slow bend propagation occurred in the presence of high concentration of SPMI. In that case, some wave parameters were preserved during the bend propagation, suggesting that these parameters should be very important to understanding the control mechanism of flagellar movement.Effects of poly amino acid on flagellar movement was studied. Only the basic and high molecular weight (15 KD or more) poly amino acids such as poly-L-lysine (PLL) inhibited the flagellar movement. The bend amplitude rather than the beat frequency was inhibited by PLL. Bends were relaxed even in the presence of high concentration of PLL. These results suggested that the inhibition manner of PLL was similar to that of SPMI in some parts. Therefore, it was likely that PLL increased the inter microtubule viscoelasticity.The microinjection of SPMI into the sea urchin blastomere was carried out. SPMI provided some inhibitory effects in a certain period prior to the cell division.