School of Horticulture, Anhui Agricultural University, Hefei 230036, Anhui, PR China.
J Exp Bot. 2011 Jan;62(3):1103-18. doi: 10.1093/jxb/erq343. Epub 2010 Nov 1.
Strawberry (Fragaria × ananassa Duch), a fruit of economic and nutritional importance, is also a model species for fleshy fruits and genomics in Rosaceae. Strawberry fruit quality at different harvest stages is a function of the fruit's metabolite content, which results from physiological changes during fruit growth and ripening. In order to investigate strawberry fruit development, untargeted (GC-MS) and targeted (HPLC) metabolic profiling analyses were conducted. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were employed to explore the non-polar and polar metabolite profiles from fruit samples at seven developmental stages. Different cluster patterns and a broad range of metabolites that exerted influence on cluster formation of metabolite profiles were observed. Significant changes in metabolite levels were found in both fruits turning red and fruits over-ripening in comparison with red-ripening fruits. The levels of free amino acids decreased gradually before the red-ripening stage, but increased significantly in the over-ripening stage. Metabolite correlation and network analysis revealed the interdependencies of individual metabolites and metabolic pathways. Activities of several metabolic pathways, including ester biosynthesis, the tricarboxylic acid cycle, the shikimate pathway, and amino acid metabolism, shifted during fruit growth and ripening. These results not only confirmed published metabolic data but also revealed new insights into strawberry fruit composition and metabolite changes, thus demonstrating the value of metabolomics as a functional genomics tool in characterizing the mechanism of fruit quality formation, a key developmental stage in most economically important fruit crops.
草莓（Fragaria × ananassa Duch）是一种具有经济和营养价值的水果，也是蔷薇科肉质果实和基因组学的模式物种。草莓果实不同成熟阶段的品质是其代谢物含量的函数，而代谢物含量则是果实生长和成熟过程中生理变化的结果。为了研究草莓果实的发育过程，我们进行了非靶向（GC-MS）和靶向（HPLC）代谢组学分析。采用主成分分析（PCA）和偏最小二乘判别分析（PLS-DA）对果实发育 7 个阶段的非极性和极性代谢物图谱进行了分析。观察到不同的聚类模式和广泛的代谢物对代谢物图谱聚类形成的影响。与红熟果实相比，转色果实和过熟果实的代谢物水平有显著变化。在红熟阶段之前，游离氨基酸水平逐渐下降，但在过熟阶段显著增加。代谢物相关性和网络分析揭示了单个代谢物和代谢途径的相互依存关系。在果实生长和成熟过程中，包括酯类生物合成、三羧酸循环、莽草酸途径和氨基酸代谢在内的几种代谢途径的活性发生了变化。这些结果不仅证实了已发表的代谢数据，还揭示了草莓果实成分和代谢物变化的新见解，从而证明了代谢组学作为一种功能基因组学工具在表征果实品质形成机制方面的价值，这是大多数经济上重要的水果作物的关键发育阶段。
