Genomic analysis of the mouse protamine 1, protamine 2, and transition protein 2 gene cluster reveals hypermethylation in expressing cells

Abstract Background Epigenetics refers to an alteration in gene expression without alteration in the sequence of DNA and this process may be affected by environmental factors and lifestyle like cigarette smoking. This study was designed to evaluate the potential effect of cigarette smoking on the global DNA methylation status and the transcription level of protamine 1 and protamine 2 in human spermatozoa. A total of 188 semen samples were collected from men with a mean age of 34.9 ± 5.8 years old (98 heavy smokers and 90 non-smokers). The DNA and RNA were isolated from purified spermatozoa, then the status of global DNA methylation and the transcription level of protamine 1 and protamine 2 were evaluated using ELISA and qPCR, respectively. The chromatin non-condensation and DNA fragmentation in human spermatozoa were evaluated using chromomycin A3 staining and TUNEL assay, respectively. Results A significant increase has been found in the status of global DNA methylation in spermatozoa of heavy smokers compared to non-smokers (7.69 ± 0.69 ng/μl vs. 4.90 ± 0.40 ng/μl, P < 0.001). Additionally, a significant reduction has been found in transcription level of protamine 1 (25.49 ± 0.31 vs. 23.94 ± 0.40, P < 0.001) and protamine 2 (28.27 ± 0.39 vs. 23.45 ± 0.30, P < 0.001) in heavy smokers. A downregulation has been found in the transcription level of protamine 1 and protamine 2 with a fold change of 0.497 and 0.047, respectively. A significant increase has been shown in the level of DNA fragmentation and chromatin non-condensation in heavy smokers compared to non-smokers (P < 0.001). On the other hand, a significant positive correlation has been found between sperm chromatin non-condensation, sperm DNA fragmentation, transcription level of protamine 1, transcription level of protamine 2, and global DNA methylation status (r = 0.304, P < 0.001; r = 0.399, P < 0.001; r = 0.216, P = 0.003; r = 0.494, P < 0.001, respectively). Conclusion Tobacco cigarette smoking has a potential influence on the global DNA methylation and the transcription level of protamine genes in human spermatozoa, and consequently, affect negatively on the semen parameters.

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Mouse protamine 2 is synthesized as a precursor whereas mouse protamine 1 is not

Molecular and Cellular Biology ◽

10.1128/mcb.7.6.2173-2179.1987 ◽

1987 ◽

Vol 7 (6) ◽

pp. 2173-2179

Author(s):

P C Yelick ◽

R Balhorn ◽

P A Johnson ◽

M Corzett ◽

J A Mazrimas ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Sequence Analysis ◽

Nucleotide Sequence ◽

Amino Acid Composition ◽

Acid Composition ◽

Nucleotide Sequence Analysis ◽

Cdna Clones ◽

Protamine 1 ◽

Protamine 2

The nuclei of mouse spermatozoa contain two protamine variants, mouse protamine 1 (mP1) and mouse protamine 2 (mP2). The amino acid sequence predicted from mP1 cDNAs demonstrates that mP1 is a 50-amino-acid protein with strong homology to other mammalian P1 protamines. Nucleotide sequence analysis of independently isolated, overlapping cDNA clones indicated that mP2 is initially synthesized as a precursor protein which is subsequently processed into the spermatozoan form of mP2. The existence of the mP2 precursor was confirmed by amino acid composition and sequence analysis of the largest of a set of four basic proteins isolated from late-step spermatids whose synthesis is coincident with that of mP1. The sequence of the first 10 amino acids of this protein, mP2 precursor 1, exactly matches that predicted from the nucleotide sequence of cDNA and genomic mP2 clones. The amino acid composition of isolated mP2 precursor 1 very closely matches that predicted from the mP2 cDNA nucleotide sequence. Sequence analysis of the amino terminus of isolated mature mP2 identified the final processing point within the mP2 precursor. These studies demonstrated that mP2 is synthesized as a precursor containing 106 amino acids which is processed into the mature, 63-amino-acid form found in spermatozoa.

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Polymorphisms in Protamine 1 and Protamine 2 predict the risk of male infertility: a meta-analysis

Scientific Reports ◽

10.1038/srep15300 ◽

2015 ◽

Vol 5 (1) ◽

Cited By ~ 13

Author(s):

Weijun Jiang ◽

Hui Sun ◽

Jing Zhang ◽

Qing Zhou ◽

Qiuyue Wu ◽

...

Keyword(s):

Male Infertility ◽

Meta Analysis ◽

Protamine 1 ◽

Protamine 2

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Magnetosome Gene Duplication as an Important Driver in the Evolution of Magnetotaxis in the Alphaproteobacteria

mSystems ◽

10.1128/msystems.00315-19 ◽

2019 ◽

Vol 4 (5) ◽

Cited By ~ 2

Author(s):

Haijian Du ◽

Wenyan Zhang ◽

Wensi Zhang ◽

Weijia Zhang ◽

Hongmiao Pan ◽

...

Keyword(s):

Gene Duplication ◽

Gene Cluster ◽

Geomagnetic Field ◽

Evolutionary Biology ◽

Genomic Analysis ◽

Magnetotactic Bacteria ◽

Duplication Event ◽

Comparative Genomic ◽

Content Type ◽

Evolutionary Trajectories

ABSTRACT The evolution of microbial magnetoreception (or magnetotaxis) is of great interest in the fields of microbiology, evolutionary biology, biophysics, geomicrobiology, and geochemistry. Current genomic data from magnetotactic bacteria (MTB), the only prokaryotes known to be capable of sensing the Earth’s geomagnetic field, suggests an ancient origin of magnetotaxis in the domain Bacteria. Vertical inheritance, followed by multiple independent magnetosome gene cluster loss, is considered to be one of the major forces that drove the evolution of magnetotaxis at or above the class or phylum level, although the evolutionary trajectories at lower taxonomic ranks (e.g., within the class level) remain largely unstudied. Here we report the isolation, cultivation, and sequencing of a novel magnetotactic spirillum belonging to the genus Terasakiella (Terasakiella sp. strain SH-1) within the class Alphaproteobacteria. The complete genome sequence of Terasakiella sp. strain SH-1 revealed an unexpected duplication event of magnetosome genes within the mamAB operon, a group of genes essential for magnetosome biomineralization and magnetotaxis. Intriguingly, further comparative genomic analysis suggests that the duplication of mamAB genes is a common feature in the genomes of alphaproteobacterial MTB. Taken together, with the additional finding that gene duplication appears to have also occurred in some magnetotactic members of the Deltaproteobacteria, our results indicate that gene duplication plays an important role in the evolution of magnetotaxis in the Alphaproteobacteria and perhaps the domain Bacteria. IMPORTANCE A diversity of organisms can sense the geomagnetic field for the purpose of navigation. Magnetotactic bacteria are the most primitive magnetism-sensing organisms known thus far and represent an excellent model system for the study of the origin, evolution, and mechanism of microbial magnetoreception (or magnetotaxis). The present study is the first report focused on magnetosome gene cluster duplication in the Alphaproteobacteria, which suggests the important role of gene duplication in the evolution of magnetotaxis in the Alphaproteobacteria and perhaps the domain Bacteria. A novel scenario for the evolution of magnetotaxis in the Alphaproteobacteria is proposed and may provide new insights into evolution of magnetoreception of higher species.

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Semen characteristics of a large cohort show protamine 1 (P1) to protamine 2 (P2) ratio is independent of other sperm parameters

Fertility and Sterility ◽

10.1016/j.fertnstert.2010.07.239 ◽

2010 ◽

Vol 94 (4) ◽

pp. S61

Author(s):

L. Nanassy ◽

D. Carrell

Keyword(s):

Large Cohort ◽

Sperm Parameters ◽

Semen Characteristics ◽

Protamine 1 ◽

Protamine 2

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Comparative genomic analysis of a mammalian β-defensin gene cluster

Physiological Genomics ◽

10.1152/physiolgenomics.00263.2006 ◽

2007 ◽

Vol 30 (3) ◽

pp. 213-222 ◽

Cited By ~ 12

Author(s):

Yashwanth Radhakrishnan ◽

Mario A. Fares ◽

Frank S. French ◽

Susan H. Hall

Keyword(s):

Positive Selection ◽

Gene Cluster ◽

Genomic Analysis ◽

Urogenital Tract ◽

Comparative Genomic ◽

Evolutionary Analysis ◽

Defensin Gene ◽

Duplication Events ◽

Molecular Evolutionary Analysis

Comparative genomic analyses have yielded valuable insights into conserved and divergent aspects of gene function, regulation, and evolution. Herein, we describe the characterization of a mouse β-defensin gene cluster locus on chromosome 2F6. In addition, we present the evolutionary analysis of this cluster and its human, rhesus, and rat orthologs. Expression analysis in mouse revealed the occurrence of defensin cluster transcripts in multiple tissues, with the highest abundance in the urogenital tract. Molecular evolutionary analysis suggests that this cluster originated by a series of duplication events, and by positive selection occurring even after the rodent-primate split. In addition, the constraints analysis showed higher positive selection in rodents than in primates, especially distal to the six-cysteine array. Positive selection in the evolution of these defensins may relate not only to the evolving enhancement of ancestral host defense but also to functional innovations in reproduction. The multiplicity of defensins and their preferential overexpression in the urogenital tract indicate that defensins function in the protection and maintenance of fertility.

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