Mejía-Flores Itzayana, Chiquete-Félix Natalia, Palma-Lara Icela, Uribe-Carvajal Salvador, de Lourdes Juárez-Mosqueda María
Departamento de Morfología,Facultad de Medicina Veterinaria y Zootecnia,UNAM.
Instituto de Fisiología Celular,UNAM,C.U.,CDMX,04510,México.
Zygote. 2017 Oct;25(5):558-566. doi: 10.1017/S0967199417000260. Epub 2017 Sep 20.
The migration pattern of sperm-specific phospholipase C-ζ (PLC-ζ) was followed and the role of this migration in actin cytoskeleton dynamics was determined. We investigated whether PLC-ζ exits sperm, opening the possibility that PLC-ζ is the 'spermatozoidal activator factor' (SOAF). As capacitation progresses, the highly dynamic actin cytoskeleton bound different proteins to regulate their location and activity. PLC-ζ participation at the start of fertilization was established. In non-capacitated spermatozoa, PLC-ζ is in the perinuclear theca (PT) and in the flagellum, therefore it was decided to determine whether bovine sperm actin interacts with PLC-ζ to direct its relocation as it progresses from non-capacitated (NC) to capacitated (C) and to acrosome-reacted (AR) spermatozoa. PLC-ζ interacted with actin in NC spermatozoa (100%), PLC-ζ levels decreased in C spermatozoa to 32% and in AR spermatozoa to 57% (P < 0.001). The level of actin/PLC-ζ interaction was twice as high in G-actin (P < 0.001) that reflected an increase in affinity. Upon reaching the AR spermatozoa, PLC-ζ was partially released from the cell. It was concluded that actin cytoskeleton dynamics control the migration of PLC-ζ during capacitation and leads to its partial release at AR spermatozoa. It is suggested that liberated PLC-ζ could reach the egg and favour fertilization.
追踪了精子特异性磷脂酶C-ζ（PLC-ζ）的迁移模式，并确定了这种迁移在肌动蛋白细胞骨架动力学中的作用。我们研究了PLC-ζ是否离开精子，这开启了PLC-ζ是“精子激活因子”（SOAF）的可能性。随着获能的进行，高度动态的肌动蛋白细胞骨架结合不同的蛋白质以调节它们的位置和活性。确定了PLC-ζ在受精开始时的参与情况。在未获能的精子中，PLC-ζ存在于核周膜（PT）和鞭毛中，因此决定确定牛精子肌动蛋白是否与PLC-ζ相互作用，以在其从未获能（NC）进展到获能（C）和顶体反应（AR）精子的过程中指导其重新定位。PLC-ζ在NC精子中与肌动蛋白相互作用（100%），在C精子中PLC-ζ水平降至32%，在AR精子中降至57%（P<0.001）。G-肌动蛋白中肌动蛋白/PLC-ζ相互作用水平高出两倍（P<0.001），这反映了亲和力的增加。到达AR精子时，PLC-ζ从细胞中部分释放。得出的结论是，肌动蛋白细胞骨架动力学在获能过程中控制PLC-ζ的迁移，并导致其在AR精子中部分释放。有人提出，释放的PLC-ζ可以到达卵子并促进受精。
