Department of Science and Technologies for Agriculture, Forestry, Nature and Energy (DAFNE), University of Tuscia, Via S.C. de Lellis snc, 01100, Viterbo, Italy.
Department of Agricultural Sciences, University of Naples Federico II, Via Università 100, 80055, Portici, Italy.
Plant Mol Biol. 2015 Oct;89(3):263-78. doi: 10.1007/s11103-015-0367-1. Epub 2015 Aug 30.
The tomato parthenocarpic fruit (pat) mutation associates a strong competence for parthenocarpy with homeotic transformation of anthers and aberrancy of ovules. To dissect this complex floral phenotype, genes involved in the pollination-independent fruit set of the pat mutant were investigated by microarray analysis using wild-type and mutant ovaries. Normalized expression data were subjected to one-way ANOVA and 2499 differentially expressed genes (DEGs) displaying a >1.5 log-fold change in at least one of the pairwise comparisons analyzed were detected. DEGs were categorized into 20 clusters and clusters classified into five groups representing transcripts with similar expression dynamics. The "regulatory function" group (685 DEGs) contained putative negative or positive fruit set regulators, "pollination-dependent" (411 DEGs) included genes activated by pollination, "fruit growth-related" (815 DEGs) genes activated at early fruit growth. The last groups listed genes with different or similar expression pattern at all stages in the two genotypes. qRT-PCR validation of 20 DEGs plus other four selected genes assessed the high reliability of microarray expression data; the average correlation coefficient for the 20 DEGs was 0.90. In all the groups were evidenced relevant transcription factors encoding proteins regulating meristem differentiation and floral organ development, genes involved in metabolism, transport and response of hormones, genes involved in cell division and in primary and secondary metabolism. Among pathways related to secondary metabolites emerged genes related to the synthesis of flavonoids, supporting the recent evidence that these compounds are important at the fruit set phase. Selected genes showing a de-regulated expression pattern in pat were studied in other four parthenocarpic genotypes either genetically anonymous or carrying lesions in known gene sequences. This comparative approach offered novel insights for improving the present molecular understanding of fruit set and parthenocarpy in tomato.
番茄单性结实果实（pat）突变与花药的同型转化和胚珠的异常有关，与单性结实的强能力有关。为了解剖这种复杂的花表型，使用微阵列分析研究了与 pat 突变体授粉无关的果实形成中涉及的基因，使用野生型和突变型卵巢。对归一化的表达数据进行了单向方差分析，在至少一对分析的成对比较中，检测到 2499 个差异表达基因（DEGs），其显示 >1.5 对数倍变化。DEGs 被分为 20 个簇，簇被分为五个组，代表具有相似表达动力学的转录本。“调节功能”组（685 个 DEGs）包含潜在的负或正果实形成调节剂，“授粉依赖”组（411 个 DEGs）包含由授粉激活的基因，“果实生长相关”组（815 个 DEGs）基因在早期果实生长时激活。最后列出的组列出了在两种基因型的所有阶段具有不同或相似表达模式的基因。对 20 个 DEGs 加上其他四个选定基因的 qRT-PCR 验证评估了微阵列表达数据的高可靠性；20 个 DEGs 的平均相关系数为 0.90。在所有组中，都有证据表明相关的转录因子编码调节分生组织分化和花器官发育的蛋白质、参与代谢、激素运输和反应的基因、参与细胞分裂以及初生和次生代谢的基因。在与次生代谢物相关的途径中，出现了与黄酮类化合物合成相关的基因，这支持了这些化合物在果实形成阶段很重要的最新证据。在其他四个单性结实基因型中，对 pat 中显示出调节表达模式的选定基因进行了研究，这些基因型在遗传上是匿名的，或者携带已知基因序列中的病变。这种比较方法为提高番茄果实形成和单性结实的现有分子理解提供了新的见解。
