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The DOI matches its Crossref record; 35 of the 35 references it cites were found in a registry or an index.

The protamine family of sperm nuclear proteins

Open access
Balhorn, Rod·2007·Genome Biology

Abstract

The protamines are a diverse family of small arginine-rich proteins that are synthesized in the late-stage spermatids of many animals and plants and bind to DNA, condensing the spermatid genome into a genetically inactive state. Vertebrates have from one to 15 protamine genes per haploid genome, which are clustered together on the same chromosome. Comparison of protamine gene and amino-acid sequences suggests that the family evolved from specialized histones through protamine-like proteins to the true protamines. Structural elements present in all true protamines are a series of arginine-rich DNA-anchoring domains (often containing a mixture of arginine and lysine residues in non-mammalian protamines) and multiple phosphorylation sites. The two protamines found in mammals, P1 and P2, are the most widely studied. P1 packages sperm DNA in all mammals, whereas protamine P2 is present only in the sperm of primates, many rodents and a subset of other placental mammals. P2, but not P1, is synthesized as a precursor that undergoes proteolytic processing after binding to DNA and also binds a zinc atom, the function of which is not known. P1 and P2 are phosphorylated soon after their synthesis, but after binding to DNA most of the phosphate groups are removed and cysteine residues are oxidized, forming disulfide bridges that link the protamines together. Both P1 and P2 have been shown to be required for normal sperm function in primates and many rodents.

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Metadata

Authors
Balhorn, R.
Venue
Genome Biology
Published
2007
Volume
8
Issue
9
Pages
227
ISSN
1465-6906 (ISSN-L)
OpenAlex
W2103336074
Cited by
773
References
35
FWCI
14.93
Type
journal article
Language
en
Open access
gold

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CoChat. (2026). Citation check: The protamine family of sperm nuclear proteins. https://app.cochat.ai/papers/10.1186/gb-2007-8-9-227
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Balhorn, R. (2007). The protamine family of sperm nuclear proteins. Genome Biology. https://doi.org/10.1186/gb-2007-8-9-227

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