Significant progress has been made in understanding carotenoid biosynthesis in tomato (Solanum lycopersicum), and most pathway genes have been cloned and characterized. However, isolation and characterization of novel fruit ripening mutants is a continuous and essential process. This study describes the characterization of the Tan⁴⁰⁶ (Tangerine⁴⁰⁶) mutant of Solanum lycopersicum. Fruits of Tan⁴⁰⁶-mutant plants have a unique orange color and accumulate prolycopene instead of lycopene. Genetic analysis revealed that a monogenic recessive mutation affects fruit pigmentation in the mutant, which inhibits the conversion of prolycopene to lycopene. Further, molecular analysis indicates that fruit phenotype is attributed to loss of CRTISO gene function, which encodes a carotenoid isomerase enzyme that converts prolycopene to lycopene. The loss of gene function is due to the deletion of 406 bp from the CRTISO promoter region. Analysis of genome-wide transcriptome expression profiling identified several hundreds of differentially expressed genes in the fruit ripening stages. The results of microarray studies showed a tendency for upregulation of the genes at the mature green stage and downregulation at the fully ripened stage in the mutant. The isolated mutant can be used for the development of varieties having altered nutritional value.

在了解番茄（ Solanum lycopersicum ）中类胡萝卜素生物合成方面已经取得了重大进展，并且大多数途径基因已被克隆和表征。然而，新型果实成熟突变体的分离和表征是一个连续且重要的过程。^{本研究描述了番茄 Tan 406} (Tangerine ⁴⁰⁶ ) 突变体的特征。Tan ⁴⁰⁶突变体植物的果实具有独特的橙色，并且积累前番茄红素而不是番茄红素。遗传分析表明，单基因隐性突变会影响突变体的果实色素沉着，从而抑制前番茄红素向番茄红素的转化。此外，分子分析表明，果实表型归因于CRTISO基因功能的丧失，该基因编码一种将前番茄红素转化为番茄红素的类胡萝卜素异构酶。基因功能的丧失是由于CRTISO启动子区域406 bp 的缺失所致。全基因组转录组表达谱分析发现了果实成熟阶段的数百个差异表达基因。微阵列研究结果表明，突变体在成熟绿色阶段基因有上调趋势，而在完全成熟阶段基因有下调趋势。分离的突变体可用于开发具有改变的营养价值的品种。