Selective sorting of ancestral introgression in maize and teosinte along an elevational cline.

While often deleterious, hybridization can also be a key source of genetic variation and pre-adapted haplotypes, enabling rapid evolution and niche expansion. Here we evaluate these opposing selection forces on introgressed ancestry between maize (Zea mays ssp. mays) and its wild teosinte relative,...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Erin Calfee, Daniel Gates, Anne Lorant, M Taylor Perkins, Graham Coop, Jeffrey Ross-Ibarra
Formato:	article
Lenguaje:	EN
Publicado:	Public Library of Science (PLoS) 2021
Materias:	Genetics QH426-470
Acceso en línea:	https://doaj.org/article/bebf20bb8608439195d5972fc307fa99
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:bebf20bb8608439195d5972fc307fa99
record_format	dspace
spelling	oai:doaj.org-article:bebf20bb8608439195d5972fc307fa992021-12-02T20:03:32ZSelective sorting of ancestral introgression in maize and teosinte along an elevational cline.1553-73901553-740410.1371/journal.pgen.1009810https://doaj.org/article/bebf20bb8608439195d5972fc307fa992021-10-01T00:00:00Zhttps://doi.org/10.1371/journal.pgen.1009810https://doaj.org/toc/1553-7390https://doaj.org/toc/1553-7404While often deleterious, hybridization can also be a key source of genetic variation and pre-adapted haplotypes, enabling rapid evolution and niche expansion. Here we evaluate these opposing selection forces on introgressed ancestry between maize (Zea mays ssp. mays) and its wild teosinte relative, mexicana (Zea mays ssp. mexicana). Introgression from ecologically diverse teosinte may have facilitated maize's global range expansion, in particular to challenging high elevation regions (> 1500 m). We generated low-coverage genome sequencing data for 348 maize and mexicana individuals to evaluate patterns of introgression in 14 sympatric population pairs, spanning the elevational range of mexicana, a teosinte endemic to the mountains of Mexico. While recent hybrids are commonly observed in sympatric populations and mexicana demonstrates fine-scale local adaptation, we find that the majority of mexicana ancestry tracts introgressed into maize over 1000 generations ago. This mexicana ancestry seems to have maintained much of its diversity and likely came from a common ancestral source, rather than contemporary sympatric populations, resulting in relatively low FST between mexicana ancestry tracts sampled from geographically distant maize populations. Introgressed mexicana ancestry in maize is reduced in lower-recombination rate quintiles of the genome and around domestication genes, consistent with pervasive selection against introgression. However, we also find mexicana ancestry increases across the sampled elevational gradient and that high introgression peaks are most commonly shared among high-elevation maize populations, consistent with introgression from mexicana facilitating adaptation to the highland environment. In the other direction, we find patterns consistent with adaptive and clinal introgression of maize ancestry into sympatric mexicana at many loci across the genome, suggesting that maize also contributes to adaptation in mexicana, especially at the lower end of its elevational range. In sympatric maize, in addition to high introgression regions we find many genomic regions where selection for local adaptation maintains steep gradients in introgressed mexicana ancestry across elevation, including at least two inversions: the well-characterized 14 Mb Inv4m on chromosome 4 and a novel 3 Mb inversion Inv9f surrounding the macrohairless1 locus on chromosome 9. Most outlier loci with high mexicana introgression show no signals of sweeps or local sourcing from sympatric populations and so likely represent ancestral introgression sorted by selection, resulting in correlated but distinct outcomes of introgression in different contemporary maize populations.Erin CalfeeDaniel GatesAnne LorantM Taylor PerkinsGraham CoopJeffrey Ross-IbarraPublic Library of Science (PLoS)articleGeneticsQH426-470ENPLoS Genetics, Vol 17, Iss 10, p e1009810 (2021)
institution	DOAJ
collection	DOAJ
language	EN
topic	Genetics QH426-470
spellingShingle	Genetics QH426-470 Erin Calfee Daniel Gates Anne Lorant M Taylor Perkins Graham Coop Jeffrey Ross-Ibarra Selective sorting of ancestral introgression in maize and teosinte along an elevational cline.
description	While often deleterious, hybridization can also be a key source of genetic variation and pre-adapted haplotypes, enabling rapid evolution and niche expansion. Here we evaluate these opposing selection forces on introgressed ancestry between maize (Zea mays ssp. mays) and its wild teosinte relative, mexicana (Zea mays ssp. mexicana). Introgression from ecologically diverse teosinte may have facilitated maize's global range expansion, in particular to challenging high elevation regions (> 1500 m). We generated low-coverage genome sequencing data for 348 maize and mexicana individuals to evaluate patterns of introgression in 14 sympatric population pairs, spanning the elevational range of mexicana, a teosinte endemic to the mountains of Mexico. While recent hybrids are commonly observed in sympatric populations and mexicana demonstrates fine-scale local adaptation, we find that the majority of mexicana ancestry tracts introgressed into maize over 1000 generations ago. This mexicana ancestry seems to have maintained much of its diversity and likely came from a common ancestral source, rather than contemporary sympatric populations, resulting in relatively low FST between mexicana ancestry tracts sampled from geographically distant maize populations. Introgressed mexicana ancestry in maize is reduced in lower-recombination rate quintiles of the genome and around domestication genes, consistent with pervasive selection against introgression. However, we also find mexicana ancestry increases across the sampled elevational gradient and that high introgression peaks are most commonly shared among high-elevation maize populations, consistent with introgression from mexicana facilitating adaptation to the highland environment. In the other direction, we find patterns consistent with adaptive and clinal introgression of maize ancestry into sympatric mexicana at many loci across the genome, suggesting that maize also contributes to adaptation in mexicana, especially at the lower end of its elevational range. In sympatric maize, in addition to high introgression regions we find many genomic regions where selection for local adaptation maintains steep gradients in introgressed mexicana ancestry across elevation, including at least two inversions: the well-characterized 14 Mb Inv4m on chromosome 4 and a novel 3 Mb inversion Inv9f surrounding the macrohairless1 locus on chromosome 9. Most outlier loci with high mexicana introgression show no signals of sweeps or local sourcing from sympatric populations and so likely represent ancestral introgression sorted by selection, resulting in correlated but distinct outcomes of introgression in different contemporary maize populations.
format	article
author	Erin Calfee Daniel Gates Anne Lorant M Taylor Perkins Graham Coop Jeffrey Ross-Ibarra
author_facet	Erin Calfee Daniel Gates Anne Lorant M Taylor Perkins Graham Coop Jeffrey Ross-Ibarra
author_sort	Erin Calfee
title	Selective sorting of ancestral introgression in maize and teosinte along an elevational cline.
title_short	Selective sorting of ancestral introgression in maize and teosinte along an elevational cline.
title_full	Selective sorting of ancestral introgression in maize and teosinte along an elevational cline.
title_fullStr	Selective sorting of ancestral introgression in maize and teosinte along an elevational cline.
title_full_unstemmed	Selective sorting of ancestral introgression in maize and teosinte along an elevational cline.
title_sort	selective sorting of ancestral introgression in maize and teosinte along an elevational cline.
publisher	Public Library of Science (PLoS)
publishDate	2021
url	https://doaj.org/article/bebf20bb8608439195d5972fc307fa99
work_keys_str_mv	AT erincalfee selectivesortingofancestralintrogressioninmaizeandteosintealonganelevationalcline AT danielgates selectivesortingofancestralintrogressioninmaizeandteosintealonganelevationalcline AT annelorant selectivesortingofancestralintrogressioninmaizeandteosintealonganelevationalcline AT mtaylorperkins selectivesortingofancestralintrogressioninmaizeandteosintealonganelevationalcline AT grahamcoop selectivesortingofancestralintrogressioninmaizeandteosintealonganelevationalcline AT jeffreyrossibarra selectivesortingofancestralintrogressioninmaizeandteosintealonganelevationalcline
_version_	1718375683849191424

Selective sorting of ancestral introgression in maize and teosinte along an elevational cline.

Ejemplares similares