Laboratory of Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
Proc Natl Acad Sci U S A. 2012 Jan 31;109(5):1542-7. doi: 10.1073/pnas.1109912109. Epub 2012 Jan 17.
Spermiogenesis is a series of poorly understood morphological, physiological and biochemical processes that occur during the transition of immotile spermatids into motile, fertilization-competent spermatozoa. Here, we identified a Serpin (serine protease inhibitor) family protein (As_SRP-1) that is secreted from spermatids during nematode Ascaris suum spermiogenesis (also called sperm activation) and we showed that As_SRP-1 has two major functions. First, As_SRP-1 functions in cis to support major sperm protein (MSP)-based cytoskeletal assembly in the spermatid that releases it, thereby facilitating sperm motility acquisition. Second, As_SRP-1 released from an activated sperm inhibits, in trans, the activation of surrounding spermatids by inhibiting vas deferens-derived As_TRY-5, a trypsin-like serine protease necessary for sperm activation. Because vesicular exocytosis is necessary to create fertilization-competent sperm in many animal species, components released during this process might be more important modulators of the physiology and behavior of surrounding sperm than was previously appreciated.
精发生成是一系列形态、生理和生化过程，发生在不动精子向能动、受精能力强的精子的转变过程中。在这里，我们鉴定了一种丝氨酸蛋白酶抑制剂（serine protease inhibitor）家族蛋白（As_SRP-1），它在猪蛔虫（Ascaris suum）精发生成（也称为精子激活）期间从精子中分泌出来，并且我们表明 As_SRP-1 具有两个主要功能。首先，As_SRP-1 在顺式起作用，以支持释放它的精子中的基于主要精子蛋白（major sperm protein，MSP）的细胞骨架组装，从而促进精子运动的获得。其次，从激活的精子中释放的 As_SRP-1 通过抑制输精管衍生的 As_TRY-5（一种激活精子所必需的胰蛋白酶样丝氨酸蛋白酶）的反式作用，抑制周围精子的激活。由于囊泡胞吐作用对于许多动物物种产生具有受精能力的精子是必要的，因此在这个过程中释放的成分可能比以前认为的更重要，是周围精子的生理和行为的调节剂。
