A model for the function of sperm DNA degradation.
In this review, we present our recent evidence suggesting, but not yet proving, that mammalian spermatozoa contain a mechanism by which they can digest their own DNA when exposed to a stressful environment. We discuss our recent data that demonstrate that when mammalian spermatozoa are treated in a variety of ways, the paternal chromosomes in the zygote, or the sperm DNA itself, are degraded into large, chromosome-sized fragments. These published data support the existence of nuclease activity in spermatozoa. We suggest that this nuclease activity is part of a mechanism the spermatozoon uses when it encounters a stressful environment to prevent fertilisation and to avoid the transmission of potentially damaged DNA to the embryo. We propose a model based on sperm chromatin structure by which this nuclease can digest the highly condensed sperm chromatin.
Ward
Monika A
MA
Institute for Biogenesis Research, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96822, USA.
Ward
W Steven
WS
D002843:Chromatin / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D015925:Cryopreservation; D004247:DNA / Q000378:metabolism*; D053938:DNA Fragmentation; D003851:Deoxyribonucleases / Q000378:metabolism*; D005298:Fertility; D006801:Humans; D008297:Male; D008954:Models, Biological; D013094:Spermatozoa / Q000201:enzymology*
D002843:Chromatin; D004247:DNA; D003851:Deoxyribonucleases