Molinero-Rosales N, Jamilena M, Zurita S, Gómez P, Capel J, Lozano R
Departamento de Biología Aplicada, Area de Genética, Universidad de Almería, 04120 Almería, Spain.
Plant J. 1999 Dec;20(6):685-93. doi: 10.1046/j.1365-313x.1999.00641.x.
Characterization of the tomato falsiflora mutant shows that fa mutation mainly alters the development of the inflorescence resulting in the replacement of flowers by secondary shoots, but also produces a late-flowering phenotype with an increased number of leaves below first and successive inflorescences. This pattern suggests that the FALSIFLORA (FA) locus regulates both floral meristem identity and flowering time in tomato in a similar way to the floral identity genes FLORICAULA (FLO) of Antirrhinum and LEAFY (LFY) of Arabidopsis. To analyse whether the fa phenotype is the result of a mutation in the tomato FLO/LFY gene, we have cloned and analysed the tomato FLO/LFY homologue (TOFL) in both wild-type and fa plants following a candidate gene strategy. The wild-type gene is predicted to encode a protein sharing 90% identity with NFL1 and ALF, the FLO/LFY-like proteins in Nicotiana and Petunia, and about 80 and 70% identity with either FLO or LFY. In the fa mutant, however, the gene showed a 16 bp deletion that results in a frameshift mutation and in a truncated protein. The co-segregation of this deletion with the fa phenotype in a total of 240 F2 plants analysed supports the idea that FA is the tomato orthologue to FLO and LFY. The gene is expressed in both vegetative and floral meristems, in leaf primordia and leaves, and in the four floral organs. The function of this gene in comparison with other FLO/LFY orthologues is analysed in tomato, a plant with a sympodial growth habit and a cymose inflorescence development.
番茄假花突变体的特征分析表明，fa突变主要改变了花序的发育，导致花朵被侧枝取代，但也产生了晚花表型，在第一和后续花序下方的叶片数量增加。这种模式表明，假花（FA）基因座以与金鱼草的花分生组织特性基因花椰菜（FLO）和拟南芥的叶状（LFY）基因相似的方式调控番茄的花分生组织特性和开花时间。为了分析fa表型是否是番茄FLO/LFY基因突变的结果，我们采用候选基因策略，在野生型和fa植株中克隆并分析了番茄FLO/LFY同源基因（TOFL）。预测野生型基因编码的蛋白质与烟草和矮牵牛中的FLO/LFY类蛋白NFL1和ALF具有90%的同一性，与FLO或LFY的同一性约为80%和70%。然而，在fa突变体中，该基因出现了16bp的缺失，导致移码突变和截短蛋白。在总共240株分析的F2植株中，这种缺失与fa表型的共分离支持了FA是番茄中FLO和LFY直系同源基因的观点。该基因在营养分生组织和花分生组织、叶原基和叶片以及四个花器官中均有表达。在具有合轴生长习性和聚伞花序发育的番茄中，分析了该基因与其他FLO/LFY直系同源基因相比的功能。
