title: The metacaspase gene family of Vitis vinifera L.: characterization and differential expression during ovule abortion in stenospermocarpic seedless grapes.
abstract: In both plants and animals, programmed cell death (PCD) is an indispensable process that removes redundant cells. In seedless grapes (Vitis vinifera), abnormal PCD in ovule cells and subsequent ovule abortion play key roles in stenospermocarpy. Metacaspase, a type of cysteine-dependent protease, plays an essential role in PCD. To reveal the characteristics of the metacaspase (MC) gene family and the relationship between metacaspases and the seedless trait, we identified the 6 V. vinifera metacaspases VvMC1-VvMC6, from the grape genome, using BLASTN against the 9 known Arabidopsis metacaspases. We also obtained full-length cDNAs by RT-PCR. Each of the 6 grape metacaspases contains small (p10-like) and a large (p20-like) conserved structural domains. Phylogenetic analysis of 6 grape and 9 Arabidopsis metacaspases showed that all metacaspases could be grouped into two classes: Type I and Type II. Each phylogenetic branch shares a similar exon/intron structure. Furthermore, the putative promoters of the grape metacaspases contained cis-elements that are involved in grape endosperm development. Moreover, expression analysis of metacaspases using real-time quantitative PCR demonstrated that VvMC1 and VvMC2 were able to be detected in any tissue, and VvMC3, VvMC4, VvMC5 and VvMC6 exhibited tissue-specific expression. Lastly, in cv. Thompson seedless grapes VvMC1, VvMC3, and VvMC4 were significantly up-regulated at the 35 DAF during ovule development, roughly same stage as endosperm abortion. In addition, the expression trend of VvMC2 and VvMC5 was similar between cv. Pinot Noir and cv. Thompson grape ovule development and that of VvMC6 was sustained in a relatively low level except the expression of cv. Pinot Noir significantly up-regulated in 25 DAF. Our data provided new insights into PCD by identifying the grape metacaspase gene family and provide a useful reference for further functional analysis of metacaspases in grape.
authors.affiliation: College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China. zhangchaohong@nwsuaf.edu.cn
authors.forename: Chaohong
authors.initials: C
authors.lastname: Zhang
authors.forename: Peijie
authors.initials: P
authors.lastname: Gong
authors.forename: Rong
authors.initials: R
authors.lastname: Wei
authors.forename: Shuxiu
authors.initials: S
authors.lastname: Li
authors.forename: Xutong
authors.initials: X
authors.lastname: Zhang
authors.forename: Yihe
authors.initials: Y
authors.lastname: Yu
authors.forename: Yuejin
authors.initials: Y
authors.lastname: Wang
mesh_terms: D020169:Caspases / Q000235:genetics* / Q000378:metabolism; D002874:Chromosome Mapping; D032461:Chromosomes, Plant / Q000235:genetics; D015870:Gene Expression; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D008969:Molecular Sequence Data; D009928:Organ Specificity; D056771:Ovule / Q000201:enzymology / Q000235:genetics* / Q000502:physiology; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012639:Seeds / Q000502:physiology; D012689:Sequence Homology, Nucleic Acid; D027843:Vitis / Q000201:enzymology / Q000235:genetics*
chemical_list: D010940:Plant Proteins; D020169:Caspases
keywords: Arabidopsis thaliana; At; DAF; DNA complementary to RNA; Metacaspase; ORF; Ovule abortion; PCD; QRT-PCR; RT-PCR; Stenospermocarpic seedlessness; Vitis vinifera; Vv; cDNA; day after full-bloom; open reading frame; programmed cell death; quantitative real-time PCR; reverse transcription PCR