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CONSTANS (CO) is the key gene in the photoperiodic pathway that regulates flowering in plants. In this paper, a CONSTANS-like 14A (COL14A) gene was obtained from mango, and its expression patterns and functions were characterized. Sequence analysis shows that MiCOL14A-JH has an additional A base, which leads to code shifting in subsequent coding boxes and loss of the CCT domain. The MiCOL14A-JH and MiCOL14A-GQ genes both belonged to group Ⅲ of the CO/COL gene family. Analysis of tissue expression patterns showed that MiCOL14A was expressed in all tissues, with the highest expression in the leaves of seedling, followed by lower expression levels in the flowers and stems of adult leaves. However, there was no significant difference between different mango varieties. At different development stages of flowering, the expression level of MiCOL14A-GQ was the highest in the leaves before floral induction period, and the lowest at flowering stage, while the highest expression level of MiCOL14A-JH appeared in the leaves at flowering stage. The transgenic functional analysis showed that both MiCOL14A-GQ and MiCOL14A-JH induced delayed flowering of transgenic Arabidopsis. In addition, MiCOL14A-JH enhanced the resistance of transgenic Arabidopsis to drought stress, while MiCOL14A-GQ increased the sensitivity of transgenic Arabidopsis to salt stress. Further proteinprotein interaction analysis showed that MiCOL14A-JH directly interacted with MYB30-INTERACTING E3 LIGASE 1 (MiMIEL1), CBL-interacting protein kinase 9 (MiCIPK9) and zinc-finger protein 4 (MiZFP4), but MiCOL14A-GQ could not interact with these three stress-related proteins. Together, our results demonstrated that MiCOL14A-JH and MiCOL14A-GQ not only regulate flowering but also play a role in the abiotic stress response in mango, and the lack of the CCT domain affects the proteinprotein interaction, thus affecting the gene response to stress. The insertion of an A base can provide a possible detection site for mango resistance breeding., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The CO/COL gene family plays an important role in regulating photoperiod-dependent flowering time in plants. In this study, two COL2 gene homologs, MiCOL2A and MiCOL2B, were isolated from 'SiJiMi' mango, and their expression patterns and functions were characterized. The MiCOL2A and MiCOL2B genes both belonged to the group Ⅰ of CO/COL gene family. MiCOL2A and MiCOL2B exhibited distinct circadian rhythms and were highly expressed in leaves during the flowering induction period. Subcellular localization analysis revealed that MiCOL2A and MiCOL2B are localized in the nucleus. The overexpression of MiCOL2A and MiCOL2B significantly delayed flowering time in Arabidopsis under both long-day (LD) and short-day (SD) conditions. The MiCOL2A and MiCOL2B overexpression Arabidopsis plants exhibited more tolerance to slat and drought stress after abiotic stress treatments, with greater ROS scavenging capacity and protective enzyme activity, less cell damage and death and higher expression of stress response genes than wild type plants. Bimolecular fluorescence complementation (BiFC) analysis showed that MiCOL2A and MiCOL2B interacted with several stress-related proteins, including zinc finger protein 4 (MiZFP4), MYB30-INTERACTING E3 LIGASE 1 (MiMIEL1) and RING zinc finger protein 34 (MiRZFP34). The results indicate that MiCOL2A and MiCOL2B are not only involved in flowering time but also play a positive role in abiotic stress responses in plants., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

APETALA1 (AP1), CAULIFLOWER (CAL) and FRUITFULL (FUL) were homologous genes with redundant functions in the process of flower transformation and floral development in Arabidopsis. Two CALs genes, MiCAL1 and MiCAL2, were cloned from mango (Mangifera indica L.). Their full-length sequences contained 717 bp and 714 bp, encoding 239 and 238 amino acids, respectively. Both the MiCAL1 and MiCAL2 proteins contained typical MADS-box and K-box domains and therefore belonged to the CAL-like protein family. MiCAL1 and MiCAL2 were expressed in all tissues at the inflorescence elongation stage and flowering stage, with the highest expression in the leaves at the flowering stage. They had similar expression patterns during flower development, with the highest expression levels in leaves during flower differentiation and the lowest expression levels during fruit development. Overexpression of MiCAL1 and MiCAL2 resulted in significantly earlier flowering in Arabidopsis. Overexpression of MiCAL1 resulted in terminal flowers with normal flower organs, while overexpression of MiCAL2 induced partially variation in floral organs but had no effect on inflorescences. Yeast two-hybrid (Y2H) experiments showed that MiCAL1 and MiCAL2 can interact with several flower-related proteins as well as stress response proteins, such as SEP1, SVP1, SVP2, SOC1G and Di19-4. These results suggest that these two MiCALs genes may have an important influence on mango flowering., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The CONSTANS-LIKE1 (COL1) gene plays an important role in the regulation of photoperiodic flowering in plants. In this study, two COL1 homolog genes, MiCOL1A and MiCOL1B, were isolated from mango (Mangifera indica L.). The open reading frames of MiCOL1A and MiCOL1B are 852 and 822 bp in length and encode 284 and 274 amino acids, respectively. The MiCOL1A and MiCOL1B proteins contain only one CCT domain and belong to the CO/COL group IV protein family. MiCOL1A and MiCOL1B were expressed both in vegetative and reproductive organs but with expression level differences. MiCOL1A was highly expressed in juvenile and adult leaves, but MiCOL1B was highly expressed in flowers. Seasonal expression analysis showed that MiCOL1A and MiCOL1B have similar expression patterns and higher expression levels during flower induction and flower organ differentiation periods. However, MiCOL1A and MiCOL1B exhibited unstable patterns in circadian expression analysis. MiCOL1A and MiCOL1B were localized in the nucleus and had transcriptional activation activity in yeast. Overexpression of MiCOL1A and MiCOL1B resulted in significantly delayed flowering time in Arabidopsis. Furthermore, we also found that overexpression of MiCOL1A and MiCOL1B enhanced drought tolerance in transgenic Arabidopsis. The results demonstrated that MiCOL1A and MiCOL1B are not only involved in flowering regulation but also play a role in the stress response of plants., (Copyright © 2022 Elsevier Masson SAS. All rights reserved.)

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: Sequence analysis showed that the encoded MiTFL1 proteins contained a conserved PEBP domain and belonged to the TFL1 group. Expression analysis showed that the MiTFL1 genes were expressed in not only vegetative organs but also reproductive organs and that the expression levels were related to floral development. Overexpression of the four MiTFL1 genes delayed flowering in transgenic Arabidopsis. Additionally, MiTFL1-1 and MiTFL1-3 changed the flower morphology in some transgenic plants. Yeast two-hybrid (Y2H) analysis showed that several stress-related proteins interacted with MiTFL1 proteins., Conclusions: The four MiTFL1 genes exhibited a similar expression pattern, and overexpression in Arabidopsis resulted in delayed flowering. Additionally, MiTFL1-1 and MiTFL1-3 overexpression affected floral organ development. Furthermore, the MiTFL1 proteins could interact with bHLH and 14-3-3 proteins. These results indicate that the MiTFL1 genes may play an important role in the flowering process in mango., (© 2021. The Author(s).)

FLOWERING LOCUS T (FT) is a key integrator of environmental signals and internal cues and plays a central role in the photoperiod response mechanism in Arabidopsis. However, the function of FTs in Mangifera indica L. is unknown. In this study, we identified three MiFTs genes from mango and characterized their role in flowering regulation. The open reading frames of MiFT1, MiFT2, and MiFT3 are 540, 516, and 588 bp in length and encode 180, 172, and 196 amino acids, respectively; the genes belong to the PEBP family. MiFTs share the conserved exon/intron structure of FTs. The nucleotide sequence of MiFT1 is 90% identical to that of MiFT2 and 82% identical to that of MiFT3; MiFT2 and MiFT3 share 81% homology with each other. According to expression analysis, MiFTs were detected at different expression levels in all tested tissues. The expression levels of the three MiFTs were significantly different in leaves during flower development, and MiFT1 expression increased sharply in leaves and was significantly higher than that of the other two MiFTs during flower bud development. All three MiFTs showed daily cycles. Ectopic expression of the three MiFTs in transgenic Arabidopsis resulted in an earlier flowering genotype under long-day conditions, and MiFT1 had the strongest effect in promoting flowering. Additionally, overexpression of three MiFTs in Arabidopsis upregulated the expression levels of several flowering-related genes. Our results suggest that the three MiFTs have positive roles in promoting flowering and suggest that MiFT1 may acts as a key regulator in the flowering pathway., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Differential display is a powerful technique for analyzing differences in gene expression. Oligo-dT cDNAstart codon targeted marker (cDNA-SCoT) technique is a novel, simple, cheap, rapid, and efficient method for differential gene expression research. In the present study, the oligo-dT anchored cDNA-SCoT technique was exploited to identify differentially expressed genes during several stress treatments in mango. A total of 37 primers combined with oligo-dT anchor primers 3side amplified approximately 150 fragments of 150 bp to 1500 bp in length. Up to 100 fragments were differentially expressed among the stress treatments and control samples, among which 92 were obtained and sequenced. Out of the 92 transcript derived fragments (TDFs), 70% were highly homologous to known genes, and 30% encoded unclassified proteins with unknown functions. The expression pattern of nine genes with known functions involved in several abiotic stresses in other species was confirmed by quantitative reverse transcription polymerase chain reaction (qRT-PCR) under cold (4 °C), salinity (NaCl), polyethylene glycol (PEG, MW 6000), and heavy metal treatments in leaves and stems at different time points (0, 24, 48, and 72 h). The expression patterns of the genes (TDF4, TDF7, TDF23, TDF45, TDF49, TDF50, TDF57, TDF91 and TDF92) that had direct or indirect relationships with cold, salinity, drought and heavy metal stress response were analyzed through qRT-PCR. The possible roles of these genes are discussed. This study suggests that the oligo-dT anchored cDNA-SCoT differential display method is a useful tool to serve as an initial step for characterizing transcriptional changes induced by abiotic stresses and provide gene information for further study and application in genetic improvement and breeding in mango., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The Rab family, the largest branch of Ras small GTPases, plays a crucial role in the vesicular transport in plants. The members of Rab family act as molecular switches that regulate the fusion of vesicles with target membranes through conformational changes. However, little is known about the Rab5 gene involved in fruit ripening and stress response. In this study, the MiRab5 gene was isolated from stress-induced Mangifera indica. The full-length cDNA sequence was 984bp and contained an open reading frame of 600bp, which encoded a 200 amino acid protein with a molecular weight of 21.83kDa and a theoretical isoelectric point of 6.99. The deduced amino acid sequence exhibited high homology with tomato (91% similarity) and contains all five characteristic Rab motifs. Real-time quantitative RT-PCR analysis demonstrated that MiRab5 was ubiquitously expressed in various mango tree tissues at different levels. The expression of MiRab5 was up-regulated during later stages of fruit ripening. Moreover, MiRab5 was generally up-regulated in response to various abiotic stresses (cold, salinity, and PEG treatments). Recombinant MiRab5 protein was successfully expressed and purified. SDS-PAGE and western blot analysis indicated that the expressed protein was recognized by the anti-6-His antibody. These results provide insights into the role of the MiRab5 gene family in fruit ripening and stress responses in the mango plant., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Abstract: Genetic variation and relationships among 47 mango germplasm and 3 relative species from Guangxi province in China, were analyzed using Start Codon Targeted (SCoT) markers. Using 33 selected SCoT primers 273 bands were generated with an average of 8.27 bands per primer among the 50 accessions, of which 208 (76.19%) were polymorphic. Genetic relationships estimated using the SM similarity coefficient generated values between different pairs of accessions that varied from 0.531 to 0.923 with an average of 0.782. These coefficients were utilized to construct a dendrogram using the UPGMA. All 50 accessions were basically classified into six clusters and correspond well with their recorded pedigrees. The results will provide much more useful information for the management of germplasm and will also be useful to improve the current breeding strategies. The results also demonstrate that the SCoT marker system is useful for identification and genetic diversity analysis of mango cultivars. [Copyright &y& Elsevier]