Both protamine-1 to protamine-2 mRNA ratio and Bcl2 mRNA content in testicular spermatids and ejaculated spermatozoa discriminate between fertile and infertile men

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.

Download Full-text

Comparison of polymorphism 139C > A ( (rs737008) of protamine 1 gene in infertile men with diagnosis of oligospermia and asthenospermia

Meta Gene ◽

10.1016/j.mgene.2021.100978 ◽

2021 ◽

pp. 100978

Author(s):

Mehdi Mohsenzadeh ◽

Aliyar Pirouzi ◽

Seyedeh Fereshteh Saadat ◽

Mahmood Dehghani Ashkezari

Keyword(s):

Infertile Men ◽

Protamine 1

Download Full-text

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.

Download Full-text

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

Download Full-text

Analysis of the ratio of α- to β-globin and globin messenger ribonucleic acid content of fractionated rabbit erythroid bone-marrow cells

Biochemical Journal ◽

10.1042/bj1790525 ◽

1979 ◽

Vol 179 (3) ◽

pp. 525-535 ◽

Cited By ~ 4

Author(s):

V A Mezl ◽

E S Kawasaki ◽

J A Hunt

Keyword(s):

Bone Marrow Cells ◽

Beta Globin ◽

Globin Mrna ◽

Constant Amount ◽

Messenger Ribonucleic Acid ◽

Mrna Ratio ◽

Linear Reaction ◽

Mrna Content ◽

Cdna Hybridization ◽

Better Than

The ratio of alpha- to beta-globin mRNA was measured by hybridization of a constant amount of highly purified alpha- or beta-globin cDNA (complementary DNA) with increasing amounts of RNA in the range up to 20% cDNA hybridization, where an essentially linear reaction is obtained. Statistical analysis indicates that the ratio of alpha- to beta-globin can be measured within a maximal error of +/- 0.3 and in most cases is better than +/- 0.15. Under these conditions there is no significant deviation from the ratio of 1.3 in the alpha- to beta-globin mRNA ratio of RNA isolated from erythroid cells rich in pronormoblasts through to reticulocytes. If the ratio of alpha- to beta-globin mRNA exceeded 1.7 or was less than 0.9 in pronormoblasts, it would be detected in these experiments. The overall globin mRNA content increases to a maximal value in the fractions rich in basophilic normoblasts of 30,000–50,000 molecules/cell. However, the accuracy of these determinations is not as great as for the ratio determinations, and no significant deviations were seen except in the cells rich in pronormoblasts, which contained less globin mRNA than the later stages.

Download Full-text