Protamine 2 Precursors and Processing

Sara      de Mateo; Liliana      Ramos; Peter      de Boer; Marvin      Meistrich; Rafael      Oliva

doi:10.2174/092986611795713998

Abstract

Protamine 2 (P2) is synthesised as a precursor protein (pre-P2) which by proteolysis is processed to generate the mature components of the protamine 2 family of proteins (HP2, HP3 and HP4). In infertile patients, abnormal processing of the protamine 2 precursors has been suggested by the detection of an increased presence of precursor forms. However, the presence of small detectable amounts of precursor proteins has been demonstrated also in normal sperm samples, although the variation of pre-P2 in individual human sperm cells had not yet been explored. In the present manuscript we perform a mini-review describing what is known about protamine 2 precursors and P2 processing. In addition, we by immunofluorescence demonstrate the existence of a marked variation in the presence and abundance of pre-P2 in individual sperm cells.

Keywords: Chromatin condensation, density gradient, histones, sperm, precursor Protamine 2, protamines, spermiogenesis, Spermatozoon, TUNEL Assay, nucleoprotamine, proteolysis, spermatids, oligospermic sperm, sonication-resistant nuclei, cytoplasmic fractions, Gene, sperm chromatin, sperm nuclear protein, Pregnancy, sperm chromatin maturationChromatin condensation, density gradient, histones, sperm, precursor Protamine 2, protamines, spermiogenesis, Spermatozoon, TUNEL Assay, nucleoprotamine, proteolysis, spermatids, oligospermic sperm, sonication-resistant nuclei, cytoplasmic fractions, Gene, sperm chromatin, sperm nuclear protein, Pregnancy, sperm chromatin maturation