IBAM   22618
INSTITUTO DE BIOLOGIA AGRICOLA DE MENDOZA
Unidad Ejecutora - UE
artículos
Título:
Catastrophic unbalanced genome rearrangements cause somatic loss of berry color in grapevine
Autor/es:
ROYO, C; CARBONELL BEJERANO, P; MARTINEZ-ZAPATER, JM; LIJAVETZKY, D
Revista:
PLANT PHYSIOLOGY.
Editorial:
AMER SOC PLANT BIOLOGISTS
Referencias:
Lugar: Rockville; Año: 2017
ISSN:
0032-0889
Resumen:
Somatic mutation is a source of diversity invegetatively propagated plants. Grape color somatic variants that can be used todevelop new grapevine cultivars occasionally appear associated to genomestructural variation (SV). To understand the mutational mechanisms generatingsomatic SV in grapevine, we compared the Tempranillo Blanco (TB) white berry somatic variant to its black berry ancestor,Tempranillo Tinto.  Whole-genomesequencing uncovered a catastrophic SV in TB that caused the hemizygousdeletion of 313 genes including the loss of the grape color locus functionalallele. Loss of heterozygosity and decreased copy number delimited interspersedmonosomic and disomic chromosome regions in the right arm of linkage groups 2and 5 of TB. At least eleven validated clustered breakpoints involving intra-and inter-chromosomal translocations between three chromosomes flanked thedeleted fragments, which are phased in a single copy of the affectedchromosomes. These hallmarks along with the lack of homology between breakpointjoins, the lack of duplicated regions and the randomness of rearrangedfragments order and orientation are all consistent with a chromothripsis-likepattern generated after breakage and illegitimate rejoining. This unbalanced genomereshuffling has additional consequences in reproductive development. In TB,lack of sexual transmission of rearranged chromosomes associated with lowgamete viability, which compromised fruit set and decreased fruit production. Ourfindings show that chromothripsis-like patterns spontaneously arise andstabilize during plant somatic growth. Despitethese dramatic changes may compromise sexual fitness, they also generate newinteresting plant features that can be perpetuated through vegetativepropagation in woody crops