Genome-Wide Analysis of the YABBY Gene Family in Grapevine and Functional Characterization of VvYABBY4

Abstract

Genes of the plant-specific YABBY transcription factor family have various roles, including lateral organ development, establishment of dorsoventral polarity, and response to abiotic stress. In this study, we carried out a genomic census of YABBY genes in grapevine (Vitis vinifera) and characterized their expression pattern during ovule development. We identified seven YABBY genes and classified them into five subfamilies, based on peptide sequence, similarity of exon–intron structure and composition of peptide sequence motifs. Analysis of YABBY gene expression in various grapevine structures and organs suggested that these genes function in diverse aspects of development and physiology. Analysis of expression during ovule development in four cultivars showed that one gene, VvYABBY4, was preferentially expressed during the period of ovule abortion in seedless cultivars. Transgenic expression of VvYABBY4 in tomato conferred reduced plant stature, dark green leaves, elongated pistil, and reduced size of fruit and seeds. Reduced seed size was associated with smaller endosperm cells. Expression of VvYABBY4 also affected expression of numerous tomato genes with presumed roles in seed development. These data suggest the potential for VvYABBY4 to influence seed development in grapevine, which may impact seedless grape breeding.

The genetic basis of sex determination in grapes

“…In A. thaliana, YABBY genes are involved in floral and lateral organ development 40 , specifically the development of carpels and the ovule outer integument 41 . Though VviYABBY3 is not yet characterized, expression of V. pseudoreticulata VpYABBY1 and VpYABBY2 in A. thaliana (and of VvYABBY4 in tomato) implicates these genes in leaf and carpel development 27,42 .…”

Genome-Wide Characterization and Expression Profiling of GASA Genes during Different Stages of Seed Development in Grapevine (Vitis vinifera L.) Predict Their Involvement in Seed Development

“…Recently, the demand for seedless grapes is also increasing [23,24]. In recent years, scientists have reported genes such as VvYABBY4 and VvHB58 as having a role in grapevine fruit and seed development [25,26]. However, the key genes mediating this process still needs to be explored, such as, for example, GASA genes.…”

Unraveling the Deep Genetic Architecture for Seedlessness in Grapevine and the Development and Validation of a New Set of Markers for VviAGL11-Based Gene-Assisted Selection

“…Later, Batillana et al [57] indicated that a VVIB23 SSR marker, contained in the 3 UTR of the YABBY gene, has specific variations associated with specific phenotypes of the flower sex locus. More recently, Zhang et al [58] showed that VvYABBY3 (from the same VVI23 locus in chromosome 2) has an increased expression at the beginning of ovule abortion and Massonnet et al [51] found that YABBY was more highly expressed in male flowers compared to female and hermaphrodite flowers at pre-blooming and anthesis stages, suggesting that YABBY is associated with female sterility in grape, inhibiting ovule development. Transgenic expression of VvYABBY4 (that has a similar expression pattern as VvYABBY3) in tomatoes conferred reduced seed sizes associated with smaller endosperm cells, but without affecting the number of seeds per fruit [58]).…”

“…More recently, Zhang et al [58] showed that VvYABBY3 (from the same VVI23 locus in chromosome 2) has an increased expression at the beginning of ovule abortion and Massonnet et al [51] found that YABBY was more highly expressed in male flowers compared to female and hermaphrodite flowers at pre-blooming and anthesis stages, suggesting that YABBY is associated with female sterility in grape, inhibiting ovule development. Transgenic expression of VvYABBY4 (that has a similar expression pattern as VvYABBY3) in tomatoes conferred reduced seed sizes associated with smaller endosperm cells, but without affecting the number of seeds per fruit [58]). In Vitis, VvβVPE, a vacuolar processing enzyme not located in chromosome 2, was described as having a caspase-1-like activity with the ability to regulate programmed cell death (PCD) and putatively playing an essential role in the development of stenospermocarpic seedless grapes ovules [59].…”