The Protective Function of Noncoding DNA in Genome Defense of Eukaryotic Male Germ Cells

Abstract

Peripheral and abundant noncoding DNA has been hypothesized to protect the genome and the central protein-coding sequences against DNA damage in somatic genome. In the cytosol, invading exogenous nucleic acids may first be deactivated by small RNAs encoded by noncoding DNA via mechanisms similar to the prokaryotic CRISPR-Cas system. In the nucleus, the radicals generated by radiation in the cytosol, radiation energy and invading exogenous nucleic acids are absorbed, blocked and/or reduced by peripheral heterochromatin, and damaged DNA in heterochromatin is removed and excluded from the nucleus to the cytoplasm through nuclear pore complexes. To further strengthen the hypothesis, this review summarizes the experimental evidence supporting the protective function of noncoding DNA in the genome of male germ cells. Based on these data, this review provides evidence supporting the protective role of noncoding DNA in the genome defense of sperm genome through similar mechanisms to those of the somatic genome.

Keywords::

• bodyguard protection
• CRISPR-like
• genome defense
• germ cells
• noncoding DNA

Acknowledgements

The authors would like to thank QIU Biqing for the critical reading of the manuscript.

Financial & competing interests disclosure

This work was supported by the Major Project of Fujian Provincial Science and Technology (2014NZ0002-3) and Longyan Scientic Scheme (2017LY73). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Additional information

Funding

This work was supported by the Major Project of Fujian Provincial Science and Technology (2014NZ0002-3) and Longyan Scientic Scheme (2017LY73). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. No writing assistance was utilized in the production of this manuscript.