Recreating stable Brachypodium hybridum allotetraploids by uniting the divergent genomes of B. distachyon and B. stacei

Thi, V.H.D. ; Coriton, O. ; Le Clainche, I. ; Arnaud, D. ; Gordon, S.P. ; Linc, G. ; Catalan, P. (Universidad de Zaragoza) ; Hasterok, R. ; Vogel, J.P. ; Jahier, J. ; Chalhoub, B.

Resumen: Brachypodium hybridum (2n = 30) is a natural allopolyploid with highly divergent subgenomes derived from two extant diploid species, B. distachyon (2n = 10) and B. stacei (2n = 20) that differ in chromosome evolution and number. We created synthetic B. hybridum allotetraploids by hybridizing various lines of B. distachyon and B. stacei. The initial amphihaploid F1 interspecific hybrids were obtained at low frequencies when B. distachyon was used as the maternal parent (0.15% or 0.245% depending on the line used) and were sterile. No hybrids were obtained from reciprocal crosses or when autotetraploids of the parental species were crossed. Colchicine treatment was used to double the genome of the F1 amphihaploid lines leading to allotetraploids. The genome-doubled F1 plants produced a few S1 (first selfed generation) seeds after self-pollination. S1 plants from one parental combination (Bd3-1×Bsta5) were fertile and gave rise to further generations whereas those of another parental combination (Bd21×ABR114) were sterile, illustrating the importance of the parental lineages crossed. The synthetic allotetraploids were stable and resembled the natural B. hybridum at the phenotypic, cytogenetic and genomic levels. The successful creation of synthetic B. hybridum offers the possibility to study changes in genome structure and regulation at the earliest stages of allopolyploid formation in comparison with the parental species and natural B. hybridum. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Idioma: Inglés

DOI: 10.1371/journal.pone.0167171

Año: 2016

Publicado en: PloS one 11, 12 (2016), 0167171[27 pp]
ISSN: 1932-6203

Factor impacto JCR: 2.806 (2016)

Categ. JCR: MULTIDISCIPLINARY SCIENCES rank: 15 / 63 = 0.238 (2016) - Q1 - T1

Factor impacto SCIMAGO: 1.236 - Agricultural and Biological Sciences (miscellaneous) (Q1) - Medicine (miscellaneous) (Q1) - Biochemistry, Genetics and Molecular Biology (miscellaneous) (Q1)

Tipo y forma: Artículo (Versión definitiva)

Área (Departamento): Área Botánica (Dpto. CC.Agrar.y Medio Natural)