Chesneau V, Prat A, Segretain D, Hospital V, Dupaix A, Foulon T, Jégou B, Cohen P
Laboratoire de Biochimie des Signaux Régulateurs Cellulaires et Moléculaires, Université Pierre et Marie Curie, Paris, France.
J Cell Sci. 1996 Nov;109 ( Pt 11):2737-45. doi: 10.1242/jcs.109.11.2737.
N-arginine dibasic convertase is a novel metalloendopeptidase which selectively cleaves at the N terminus of arginine residues in paired basic amino acids. Although present in brain and several other tissues, NRD convertase is particularly abundant in testis, where its expression appeared to be restricted to germ cells. Low levels of both mRNA and its corresponding protein were detected early in spermatogenesis. However, a marked accumulation of the protein was observed during late steps (14 to 19) of spermiogenesis. By electron microscopy, the NRD convertase immunoreactivity was localized in the cytoplasm of elongating and elongated spermatids, with a noticeable concentration at the level of two microtubular structures, i.e. the manchette and the axoneme. These observations strongly support the hypothesis that NRD convertase is involved in processing events potentially associated with the morphological transformations occurring during spermiogenesis.
N-精氨酸二肽基转换酶是一种新型金属内肽酶，它能选择性地在成对碱性氨基酸中精氨酸残基的N端进行切割。尽管在脑和其他几种组织中都有存在，但NRD转换酶在睾丸中特别丰富，其表达似乎仅限于生殖细胞。在精子发生早期检测到mRNA及其相应蛋白质的水平都很低。然而，在精子形成后期步骤（14至19）中观察到该蛋白质有明显积累。通过电子显微镜观察，NRD转换酶免疫反应性定位于伸长和成熟精子细胞的细胞质中，在两个微管结构即环行片层和轴丝水平有明显聚集。这些观察结果有力地支持了这样一种假说，即NRD转换酶参与了可能与精子形成过程中发生的形态转变相关的加工事件。
