Cáceres C, Giménez-Bonafé P, Ribes E, Wouters-Tyrou D, Martinage A, Kouach M, Sautière P, Muller S, Palau J, Subirana J A, Cornudella L, Chiva M
Departament d'Enginyeria Química, Escola Tècnica Superior d'Enginyers Industrials de Barcelona, Universitat Politècnica de Catalunya, Diagonal 647, 08028 Barcelona, Spain.
J Biol Chem. 1999 Jan 8;274(2):649-56. doi: 10.1074/jbc.274.2.649.
Sperm chromatin of Murex brandaris (a neogastropod mollusc) undergoes a series of structural transitions during spermiogenesis. The DNA-interacting proteins responsible for these changes as well as the mature protamines present in the ripe sperm nucleus have been characterized. The results reveal that spermiogenic nuclear proteins are protamine precursors that are subjected to a substantial number of small N-terminal deletions that gradually modify their overall charge. The composition of mature protamines is remarkably simple in turn, promoting an efficient and extremely tight packaging of DNA. The pattern of spermiogenic chromatin condensation in M. brandaris clearly departs from that corresponding to vertebrate chromatin.
红螺（一种新腹足类软体动物）的精子染色质在精子发生过程中经历了一系列结构转变。负责这些变化的与DNA相互作用的蛋白质以及成熟精子核中存在的鱼精蛋白已得到表征。结果表明，精子发生核蛋白是鱼精蛋白前体，它们经历了大量的N端小缺失，从而逐渐改变其整体电荷。反过来，成熟鱼精蛋白的组成非常简单，促进了DNA的高效且极其紧密的包装。红螺精子发生染色质浓缩模式明显不同于脊椎动物染色质的模式。
