Altered protamine expression and diminished spermatogenesis: what is the link?

Douglas T. Carrell; Benjamin R. Emery; Sue Hammoud
May 2007
Human Reproduction Update;May2007, Vol. 13 Issue 3, p313
Academic Journal
During the elongating spermatid stage of spermiogenesis, human sperm chromatin undergoes a complex transition in which histones are extensively replaced by protamines in a carefully regulated transition including histone modifications and intermediate and temporary replacement of the histones by sperm-specific transition proteins. The replacement of most histones by protamines 1 and 2 facilitates a high order of chromatin packaging necessary for normal sperm function and may also be necessary for DNA silencing and imprinting changes within the sperm cell. Protamines 1 and 2 are usually expressed in nearly equal quantities, but elevated or diminished protamine 1/protamine 2 ratios are observed in some infertile men and is often associated with severe spermatogenesis defects. Human and animal studies demonstrate that expression of the protamine proteins is uniquely regulated by transcription/translation factors, including storage of the mRNA in ribonucleoprotein (RNP) particles composed of the mRNA, transcription factors and a kinesin molecule necessary for transport of the RNP to the cytoplasm and removal of transcriptional activators from the nucleus. Recent studies indicate that most patients with abnormal protamine protein levels have elevated levels of protamine transcript in the mature sperm cell, indicating a possible defect in transcription or translation. The regulation of protamine expression is unique and includes several possible mechanisms which may be responsible for dysregulation of protamine expression and concurrent broad spectrum defects in spermatogenesis. We suggest two hypotheses: (i) that abnormal protamine expression is indicative of a generalized defect in mRNA storage and/or translation which affects other mRNA transcripts or (ii) that protamines may act as a checkpoint of spermatogenesis.


Related Articles

  • THE TESTS-SPECIFIC LINKER HISTONE H1T NOT ESSENTIAL FOR SPERMATOGENESIS. Qingcong Lin; Skoultchi, Arthur I. // Einstein Quarterly: Journal of Biology & Medicine;1998, Vol. 15 Issue 2, p111 

    Investigates the role of H1t histones in spermatogenesis. Replacement of H1 histones by transition proteins and protamines during later stages of spermatogenesis; Function of H1 histones in the packaging of chromatin; Ratio of total H1 histones to nucleosomes in the H1t deficient animals;...

  • Sperm-derived histones contribute to zygotic chromatin in humans. van der Heijden, Godfried W.; Ramos, Liliana; Baart, Esther B.; van den Berg, Ilse M.; Derijck, Alwin A. H. A.; van der Vlag, Johan; Martini, Elena; de Boer, Peter // BMC Developmental Biology;2008, Vol. 8, Special section p1 

    Background: about 15% to 30% of the DNA in human sperm is packed in nucleosomes and transmission of this fraction to the embryo potentially serves as a mechanism to facilitate paternal epigenetic programs during embryonic development. However, hitherto it has not been established whether these...

  • Repressive and active histone methylation mark distinct promoters in human and mouse spermatozoa. Brykczynska, Urszula; Hisano, Mizue; Erkek, Serap; Ramos, Liliana; Oakeley, Edward J.; Roloff, Tim C.; Beisel, Christian; Schübeler, Dirk; Stadler, Michael B.; Peters, Antoine H. F. M. // Nature Structural & Molecular Biology;Jun2010, Vol. 17 Issue 6, p679 

    In higher eukaryotes, histone methylation is involved in maintaining cellular identity during somatic development. As most nucleosomes are replaced by protamines during spermatogenesis, it is unclear whether histone modifications function in paternal transmission of epigenetic information. Here...

  • Deficiencies in the Process may Alter Correct Epigenetic Programming in Mature Sperm.  // Fertility Weekly;3/17/2014, p10 

    The article focuses on a study which examines the effects of deficiencies during spermatogenesis for proper epigenetic programming of mature sperm. It says that the study has conducted examination involving seminal ejaculates derive from 39 normozoospermic men, in which semen were analyzed to...

  • Cloning and Functional Analysis of Histones H3 and H4 in Nuclear Shaping during Spermatogenesis of the Chinese Mitten Crab, Eriocheir sinensis. Wu, Jiang-Li; Kang, Xian-Jiang; Guo, Ming-Shen; Mu, Shu-Mei; Zhang, Zhao-Hui // PLoS ONE;May2015, Vol. 10 Issue 5, p1 

    During spermatogenesis in most animals, the basic proteins associated with DNA are continuously changing and somatic-typed histones are partly replaced by sperm-specific histones, which are then successively replaced by transition proteins and protamines. With the replacement of sperm nuclear...

  • Gene expression analysis of H2B histone variant hTSH2B in testis tissues of non-obstructive azoospermic patients referred to Royan Institute. Faghihi Zohani, F.; Shahhoseini, M.; Favaedi, R.; Sadighi Gilani, M. A.; Shahzadeh Fazeli, A. // Iranian Journal of Reproductive Medicine;AprSupp, p44 

    Introduction: 50% of infertility causes are because of male factors. Infertility in men usually is due to impaired spermatogenesis process. Human testis/sperm-specific histone H2B (hTSH2B) is a histone H2B variant specifically expressed in human testis tissues, from spermatogonia to mature...

  • MNS1 Is Essential for Spermiogenesis and Motile Ciliary Functions in Mice. Jian Zhou; Fang Yang; Leu, N. Adrian; Wang, P. Jeremy // PLoS Genetics;Mar2012, Vol. 8 Issue 3, Special section p1 

    During spermiogenesis, haploid round spermatids undergo dramatic cell differentiation and morphogenesis to give rise to mature spermatozoa for fertilization, including nuclear elongation, chromatin remodeling, acrosome formation, and development of flagella. The molecular mechanisms underlining...

  • Chromatin condensation and DNA damage of human epididymal spermatozoa in obstructive azoospermia. Ramos, L.; De Boer, P.; Meuleman, E. J. H.; Braat, D. D. M.; Wetzels, A. M. M. // Reproductive BioMedicine Online (Reproductive Healthcare Limited;Apr2004, Vol. 8 Issue 4, p392 

    Obstructive azoospermia (OA) includes patients with different aetiologies of obstruction such as congenital bilateral absence of vas deferens (CBAVD), post-vasectomy/failed vaso-vasostomy, or unknown (idiopathic). The frequency of DNA-damaged spermatozoa and abnormal chromatin condensation in...

  • Seminal and molecular evidence that sauna exposure affects human spermatogenesis. Garolla, Andrea; Torino, Mario; Sartini, Barbara; Cosci, Ilaria; Patassini, Cristina; Carraro, Umberto; Foresta, Carlo // Human Reproduction;Apr2013, Vol. 28 Issue 4, p877 

    STUDY QUESTION What are the effects of continuous sauna exposure on seminal parameters, sperm chromatin, sperm apoptosis and expression of genes involved in heat stress and hypoxia? SUMMARY ANSWER Scrotal hyperthermia by exposure to sauna can induce a significant alteration of spermatogenesis....


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics