ABSTRACT Male infertility is a long-standing enigma of significant medical concern. The integrity of sperm chromatin is a clinical indicator of male fertility and _in vitro_ fertilization

potential1: chromosome aneuploidy and DNA decondensation or damage are correlated with reproductive failure. Identifying conserved proteins important for sperm chromatin structure and

packaging can reveal universal causes of infertility. Here we combine proteomics, cytology and functional analysis in _Caenorhabditis elegans_ to identify spermatogenic chromatin-associated

proteins that are important for fertility. Our strategy employed multiple steps: purification of chromatin from comparable meiotic cell types, namely those undergoing spermatogenesis or

extensive catalogue, to 132 proteins for functional analysis. Reduction of gene function through RNA interference coupled with protein localization studies revealed conserved

spermatogenesis-specific proteins vital for DNA compaction, chromosome segregation, and fertility. Unexpected roles in spermatogenesis were also detected for factors involved in other

processes. Our strategy to find fertility factors conserved from _C. elegans_ to mammals achieved its goal: of mouse gene knockouts corresponding to nematode proteins, 37% (7/19) cause male

sterility. Our list therefore provides significant opportunity to identify causes of male infertility and targets for male contraceptives. Access through your institution Buy or subscribe

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ZINC IS A MASTER-REGULATOR OF SPERM FUNCTION ASSOCIATED WITH BINDING, MOTILITY, AND METABOLIC MODULATION DURING PORCINE SPERM CAPACITATION Article Open access 03 June 2022 CEP112 COORDINATES

TRANSLATIONAL REGULATION OF ESSENTIAL FERTILITY GENES DURING SPERMIOGENESIS THROUGH PHASE SEPARATION IN HUMANS AND MICE Article Open access 30 September 2024 HIGHLY CONSERVED SHIFTS IN

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ACKNOWLEDGEMENTS We thank S. Strome, K. Bennett, H.-S. Koo, L. Moore, E. Shulze and J. Aris for providing antibodies; A. Villenueve, G. Stanfield, S. Mitani and the _C. elegans_ Genetic

Center (CGC) for providing strains; V. Reinke, L. Moore and R. Navarro for sharing unpublished data; D. King for peptide synthesis; A. Chan for help with microscopy; S. Chu for statistical

analysis; A. Severson, T. Cline, A. Skop, E. Xu and J. Gladden for comments on the manuscript; and members of the Meyer laboratory for input on this project. This work was funded by the

National Institutes of Health grants to D.S.C., J.R.Y. and B.J.M. B.J.M. is an investigator of the Howard Hughes Medical Institute. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department

of Biology, San Francisco State University, 1600 Holloway Avenue, California, 94132, San Francisco, USA Diana S. Chu & Tammy F. Wu * Department of Cell Biology, The Scripps Research

Institute, 10550 North Torrey Pines Road, California, 92037, La Jolla, USA Hongbin Liu & John R. Yates III * Agilent Technologies, Inc., 2850 Centerville Road, Delaware, 19808,

Wilmington, USA Hongbin Liu * Department of Molecular and Cell Biology, University of California, Berkeley, California, 94720, Berkeley, USA Paola Nix, Edward J. Ralston & Barbara J.

Meyer * Howard Hughes Medical Institute, California, 94720, Berkeley, USA Paola Nix, Edward J. Ralston & Barbara J. Meyer Authors * Diana S. Chu View author publications You can also

search for this author inPubMed Google Scholar * Hongbin Liu View author publications You can also search for this author inPubMed Google Scholar * Paola Nix View author publications You can

also search for this author inPubMed Google Scholar * Tammy F. Wu View author publications You can also search for this author inPubMed Google Scholar * Edward J. Ralston View author

publications You can also search for this author inPubMed Google Scholar * John R. Yates III View author publications You can also search for this author inPubMed Google Scholar * Barbara J.

Meyer View author publications You can also search for this author inPubMed Google Scholar CORRESPONDING AUTHOR Correspondence to Diana S. Chu. ETHICS DECLARATIONS COMPETING INTERESTS

Reprints and permissions information is available at www.nature.com/reprints. The authors declare no competing financial interests. SUPPLEMENTARY INFORMATION SUPPLEMENTARY NOTES This file

contains Supplementary Methods that contain additional detailed methods used in the paper, Supplementary references, legends for Supplementary Figs 1–5 and a legend for Supplementary Table

6. (DOC 112 kb) SUPPLEMENTARY FIGURES This file contains Supplementary figures 1–5. (PDF 1188 kb) SUPPLEMENTARY TABLE 1 Abundant spermatogenesis-enriched proteins copurified with chromatin

identified by comparative proteomic analysis. (PDF 68 kb) SUPPLEMENTARY TABLE 2 Low abundance spermatogenic proteins copurified with chromatin identified by comparative proteomic analysis

(PDF 102 kb) SUPPLEMENTARY TABLE 3 All shared proteins copurified with chromatin identified by comparative proteomic analysis. (PDF 139 kb) SUPPLEMENTARY TABLE 4 Oogenic proteins copurified

with chromatin identified by comparative proteomic analysis. (PDF 87 kb) SUPPLEMENTARY TABLE 5 This table lists the composition of identified proteins from spermatogenic chromatin samples in

functional categories. (PDF 34 kb) SUPPLEMENTARY TABLE 6 This table summarizes defects for genes found to be important for fertility by RNAi analysis. (PDF 61 kb) SUPPLEMENTARY TABLE 7 This

table lists abundant spermatogenesis-enriched chromatin proteins with function in C. elegans fertility. The protein localization has not yet been determined in C. elegans (Category III

proteins). Mouse and human homologs with a minimum E value of 1e-9 are listed. (PDF 62 kb) SUPPLEMENTARY TABLE 8 The table lists abundant C. elegans spermatogenesis-enriched chromatin

proteins homologous to mammalian fertility factors. Mouse and human homologs with a minimum E value of 1e-9 are listed. (PDF 62 kb) SUPPLEMENTARY TABLE 9 This table lists abundant C. elegans

spermatogenesis-enriched chromatin proteins with mammalian homologs not yet linked to fertility. Mouse and human homologs with a minimum E value of 1e-9 are listed. (PDF 80 kb) RIGHTS AND

PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Chu, D., Liu, H., Nix, P. _et al._ Sperm chromatin proteomics identifies evolutionarily conserved fertility factors.

_Nature_ 443, 101–105 (2006). https://doi.org/10.1038/nature05050 Download citation * Received: 21 April 2006 * Accepted: 06 July 2006 * Published: 30 August 2006 * Issue Date: 07 September

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