Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2018 Jun 18;9(1):2370.
doi: 10.1038/s41467-018-04562-5.

High-resolution Crossover Mapping Reveals Similarities and Differences of Male and Female Recombination in Maize

Affiliations
Free PMC article

High-resolution Crossover Mapping Reveals Similarities and Differences of Male and Female Recombination in Maize

Penny M A Kianian et al. Nat Commun. .
Free PMC article

Abstract

Meiotic crossovers (COs) are not uniformly distributed across the genome. Factors affecting this phenomenon are not well understood. Although many species exhibit large differences in CO numbers between sexes, sex-specific aspects of CO landscape are particularly poorly elucidated. Here, we conduct high-resolution CO mapping in maize. Our results show that CO numbers as well as their overall distribution are similar in male and female meioses. There are, nevertheless, dissimilarities at local scale. Male and female COs differ in their locations relative to transcription start sites in gene promoters and chromatin marks, including nucleosome occupancy and tri-methylation of lysine 4 of histone H3 (H3K4me3). Our data suggest that sex-specific factors not only affect male-female CO number disparities but also cause fine differences in CO positions. Differences between male and female CO landscapes indicate that recombination has distinct implications for population structure and gene evolution in male and in female meioses.

Conflict of interest statement

The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
CO landscape of chromosome 7. See Supplementary Fig. 3 for other chromosomes. Blue = male COs, red = female COs. Colors on the X-axis indicate chromosome regions: purple = functional centromeres (=CENH3-binding regions), black = centromere repeats, gray = pericentromeric regions, light gray = distal regions. Insets are cumulative genetic distances across entire chromosomes. Gray triangles in insets are supplemental SNPs added, where needed, to create 1 Mbp intervals. Figures were generated using MareyMap
Fig. 2
Fig. 2
Comparison of DNA sequence motifs associated with CO sites in male and female meioses in the B73 × Mo17 hybrid. Probability values are log–likelihood ratios
Fig. 3
Fig. 3
Relationship of COs sites to genome and chromatin features in male and female meioses. a Position of COs relative to TEs and protein coding genes. b Position of COs in the 5′ and 3′ regions of genes. c DNA methylation patterns around CO sites at CG, CHG, and CHH sites. d H3K4me3 levels of CO sites in male and female meioses. e Nucleosome occupancy of CO sites in male and female meioses measured using micrococcal nuclease sensitivity. f Boxplot showing transcription levels of CO-containing genes in male meiocytes and seedlings. Center lines of boxes represent median expression levels, bounds of boxes designate expression levels of the first (Q1) and third (Q3) quartiles from top, lower whiskers are Q1 – 1.5 × IQR, and upper whiskers are Q3 – 1.5 × IQR, where IQR = Q3 – Q1
Fig. 4
Fig. 4
Recombination and chromatin features at knobs and chromosome ends. All regions were equalized to the same size and divided into 100 bins for analysis, except nucleosome occupancy, which was divided into 30 bins to improve readability of the graph. The five knobs mapped in B73 are shown. The sixth knob present in B73 and the single knob present in Mo17 are not anchored to the maize genome scaffold and were not analyzed

Similar articles

See all similar articles

Cited by 9 articles

See all "Cited by" articles

References

    1. Mézard C, Tagliaro Jahns M, Grelon M. Where to cross? New insights into the location of meiotic crossovers. Trends Genet. 2015;31:393–401. doi: 10.1016/j.tig.2015.03.008. - DOI - PubMed
    1. Pawlowski WP, et al. Coordination of meiotic recombination, pairing, and synapsis by PHS1. Science. 2004;303:89–92. doi: 10.1126/science.1091110. - DOI - PubMed
    1. Mercier R, Mézard C, Jenczewski E, Macaisne N, Grelon M. The molecular biology of meiosis in plants. Annu. Rev. Plant. Biol. 2015;66:297–327. doi: 10.1146/annurev-arplant-050213-035923. - DOI - PubMed
    1. Jones GH, Franklin FCH. Meiotic crossing-over: obligation and interference. Cell. 2006;126:246–248. doi: 10.1016/j.cell.2006.07.010. - DOI - PubMed
    1. Sidhu GK, et al. Recombination patterns in maize reveal limits to crossover homeostasis. Proc. Natl Acad. Sci. USA. 2015;112:15982–15987. doi: 10.1073/pnas.1514265112. - DOI - PMC - PubMed

Publication types

Feedback