The Overexpression of Four MiTFL1 Genes from Mango Delays the Flowering Time in Transgenic Arabidopsis

Abstract

Background: TERMINAL FLOWER 1 (TFL1) belongs to the phosphatidylethanolamine-binding protein (PEBP) family, which is involved in inflorescence meristem development and represses flowering in several plant species. In the present study, four TFL1 genes were cloned from the mango (Mangifera indica L.) variety ‘SiJiMi’ and named MiTFL1-1, MiTFL1-2, MiTFL1-3 and MiTFL1-4.Results: A sequence analysis showed that the encoded MiTFL1 proteins contained a conserved PEBP domain and belonged to the TFL1 group. The expression of the MiTFL1 genes was examined in several tissues, including juvenile leaves, mature leaves, mature stems, and flowers. The highest MiTFL1 expression level was detected in mature stems followed by juvenile leaves but was lower in mature leaves and flowers during the flowering period. Further expression studies showed that MiTFL1s were highly expressed in leaves during the floral induction and differentiation periods. Overexpression of the four MiTFL1 genes delayed the flowering time in transgenic Arabidopsis. The results also showed that MiTFL1-1 and MiTFL1-3 could change the flower morphology in some transgenic plants. Yeast two-hybrid analysis showed that several stress-related proteins can interact with MiTFL1s.Conclusions: Four MiTFL1 genes exhibit a similar expression pattern, and overexpressed in Arabidopsis resulted in delayed flowering. In addition, MiTFL1-1 and MiTFL1-3 overexpression affected floral organ development. MiTFL1s can interact with bHLH and 14-3-3 proteins. These results indicate that MiTFL1s might play an important role in the flowering process in mango.

Genome-wide identification of the mango CONSTANS (CO) family and functional analysis of two MiCOL9 genes in transgenic Arabidopsis

“…Agrobacterium tumefaciens (EHA105) containing positive recombinant plasmids was transformed into Arabidopsis (Col-0) plants with the floral-dip method ( Clough and Bent, 1998 ). For the third-generation (T3) homozygous positive transformants, RNA was extracted for semiquantitative RT–PCR (SqRT-PCR)-based analysis before flowering ( Wang et al., 2021 ), and the flowering-related genes AtFT , AtSOC1 and AtFLC were used for qRT−PCR analysis ( Table S1 ). AtActin2 was used as a reference control.…”