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In flowering plants, floral homeotic MADS-box genes, which constitute a large multigene family, play important roles in the specification of floral organs as defined by the ABCDE model. In this study, a MADS-box gene, ZjMADS1, was...
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In flowering plants, floral homeotic MADS-box genes, which constitute a large multigene family, play important roles in the specification of floral organs as defined by the ABCDE model. In this study, a MADS-box gene, ZjMADS1, was isolated and characterized from the marine angiosperm Zostera japonica. The predicted length of the ZjMADSI protein was 246 amino acids (AA), and the AA sequence was most similar to those of the SEPALLATA (SEP) subfamily, corresponding to E-function genes. Southern blot analysis suggested the presence of two SEP3-like genes in the Z. japonica genome. ZjMADSI mRNA levels were extremely high in the spadices, regardless of the developmental stage, compared to other organs from the reproductive and vegetative shoots. These results suggest that the ZjMADSI gene may be involved in spadix development in Z. japonica and act as an E-function gene in floral organ development in marine angiosperms.
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Land plants (embryophytes) are characterized by an alternation of two generations, the haploid gametophyte and the diploid sporophyte. The development of the small and simple male gametophyte of the flowering plant Arabidopsis (Ar...
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Land plants (embryophytes) are characterized by an alternation of two generations, the haploid gametophyte and the diploid sporophyte. The development of the small and simple male gametophyte of the flowering plant Arabidopsis (Arabidopsis thaliana) critically depends on the action of five MIKC* group MCM1-AGAMOUS-DEFICIENS-SRF-box (MADS-box) proteins. In this study, these MIKC* MADS-box genes were isolated from land plants with relatively large and complex gametophyte bodies, namely the bryophytes. We found that although the gene family expanded in the mosses Sphagnum subsecundum, Physcomitrella patens, and Funaria hygrometrica, only a single homologue, Marchantia polymorpha MADS-box gene 1 (MpMADS1), has been retained in the liverwort M. polymorpha. Liverworts are the earliest diverging land plants, and so a comparison of MpMADS1 with its angiosperm homologues addresses the molecular evolution of an embryophyte-specific transcription factor over the widest phylogenetic distance. MpMADS1 was found to form a homodimeric DNA-binding complex, which is in contrast to the Arabidopsis proteins that are functional only as heterodimeric complexes. The M. polymorpha homodimer, nevertheless, recognizes the same DNA sequences as its angiosperm counterparts and can functionally replace endogenous MIKC* complexes to a significant extent when heterologously expressed in Arabidopsis pollen. The 11 MIKC* homologues from the moss F. hygrometrica are highly and almost exclusively expressed in the gametophytic generation. Taken together, these findings suggest that MIKC* MADS-box proteins have largely preserved molecular roles in the gametophytic generation of land plants.
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Методом прямой амплификации геномной ДНК, выделенной из двух сортов сарепгской горчицы (Brassica juncea), получены два гомолога MADS-box...
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Методом прямой амплификации геномной ДНК, выделенной из двух сортов сарепгской горчицы (Brassica juncea), получены два гомолога MADS-box гена FLOWERING LOCUS C, который контролирует продолжительность периода до цветения у растений арабидопсиса. Нуклеотидные и производные аминокислотные последовательности двух клонированных фрагментов FLC (со 2 по 7 экзон) сопоставлены с ранее охарактеризованными генами FLC у арабидопсиса и его гомологами у других видов Brassicaceae. Гомолог AY266265 является ортологом гена FLC3 Brassicarapa (95% гомологии), а функциональная принадлежность гомолога AY268931 окончательно не установлена На примере гена FLC и его гомологов оценена сравни тельная изменчивость первичного строения экзонов и нитронов .
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Flower development in kiwifruit {Actinidia spp.) is initiated in the first growing season, when undifferentiated primordia are established in axillary shoot buds. These primordia can differentiate into flowers in the second growin...
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Flower development in kiwifruit {Actinidia spp.) is initiated in the first growing season, when undifferentiated primordia are established in axillary shoot buds. These primordia can differentiate into flowers in the second growing season, after the winter dormancy period and upon accumulation of adequate winter chilling. Insufficient winter chilling results in poor budbreak, reduced flowering and reduced fruit yield. Members of the MADS-box gene family of transcription factors have demonstrated roles in inflorescence and flower development and have flower-promoting or repressing functions. In the model plant Arabidopsis thaliana, the vernalization requirement is largely conferred by the MADS-box gene FLOWERING LOCUS C {FLC), a member of a small gene family that also contains five MADS AFFECTING FLOWERING {MAF) genes, all thought to function as repressors of flowering. It is unclear if the FLC-mediated vernalization response is restricted to the Brassicaceae. Our aim is to establish the role of FLC-\ike genes in dormancy, budbreak and flowering of kiwifruit.
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MADS-box transcription factors (TFs) are involved in multiple plant development processes and are most known during the reproductive transition and floral organ development. Very few genes have been characterized in the genome of ...
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MADS-box transcription factors (TFs) are involved in multiple plant development processes and are most known during the reproductive transition and floral organ development. Very few genes have been characterized in the genome of Humulus lupulus L. (Cannabaceae), an important crop for the pharmaceutical and beverage industries. The MADS-box family has not been studied in this species yet. We identified 65 MADS-box genes in the hop genome, of which 29 encode type-II TFs (27 of subgroup MIKCC and 2 MIKC*) and 36 type-I proteins (26 α, 9 β, and 1 γ). Type-II MADS-box genes evolved more complex architectures than type-I genes. Interestingly, we did not find FLOWERING LOCUS C (FLC) homologs, a transcription factor that acts as a floral repressor and is negatively regulated by cold. This result provides a molecular explanation for a previous work showing that vernalization is not a requirement for hop flowering, which has implications for its cultivation in the tropics. Analysis of gene ontology and expression profiling revealed genes potentially involved in the development of male and female floral structures based on the differential expression of ABC homeotic genes in each whorl of the flower. We identified a gene exclusively expressed in lupulin glands, suggesting a role in specialized metabolism in these structures. In toto, this work contributes to understanding the evolutionary history of MADS-box genes in hop, and provides perspectives on functional genetic studies, biotechnology, and crop breeding.
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Members of the MADS-box transcription factor family play essential roles in almost every developmental process in plants. Many MADS-box genes have conserved functions across the flowering plants, but some have acquired novel funct...
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Members of the MADS-box transcription factor family play essential roles in almost every developmental process in plants. Many MADS-box genes have conserved functions across the flowering plants, but some have acquired novel functions in specific species during evolution. The analyses of MADS-domain protein interactions and target genes have provided new insights into their molecular functions. Here, we review recent findings on MADS-box gene functions in Arabidopsis and discuss the evolutionary history and functional diversification of this gene family in plants. We also discuss possible mechanisms of action of MADS-domain proteins based on their interactions with chromatin-associated factors and other transcriptional regulators.
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The MADS-box transcription factor family has expanded considerably in plants via gene and genome duplications and can be subdivided into type I and MIKC-type genes. The two gene classes show a different evolutionary history. Where...
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The MADS-box transcription factor family has expanded considerably in plants via gene and genome duplications and can be subdivided into type I and MIKC-type genes. The two gene classes show a different evolutionary history. Whereas the MIKC-type genes originated during ancient genome duplications, as well as during more recent events, the type I loci appear to experience high turnover with many recent duplications. This different mode of origin also suggests a different fate for the type I duplicates, which are thought to have a higher chance to become silenced or lost from the genome. To get more insight into the evolution of the type I MADS-box genes, we isolated nine type I genes from Petunia, which belong to the Mγ subclass, and investigated the divergence of their coding and regulatory regions. The isolated genes could be subdivided into two categories: two genes were highly similar to Arabidopsis Mγ-type genes, whereas the other seven genes showed less similarity to Arabidopsis genes and originated more recently. Two of the recently duplicated genes were found to contain deleterious mutations in their coding regions, and expression analysis revealed that a third paralog was silenced by mutations in its regulatory region. However, in addition to the three genes that were subjected to nonfunctionalization, we also found evidence for neofunctionalization of one of the Petunia Mγ-type genes. Our study shows a rapid divergence of recently duplicated Mγ-type MADS-box genes and suggests that redundancy among type I paralogs may be less common than expected.
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As an important food crop and oil crop, soybean ( Glycine max [L.] Merr.) is capable of nitrogen-fixing by root nodule. Previous studies showed that GmNMH7, a transcription factor of MADS-box family, is associated with nodule deve...
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As an important food crop and oil crop, soybean ( Glycine max [L.] Merr.) is capable of nitrogen-fixing by root nodule. Previous studies showed that GmNMH7, a transcription factor of MADS-box family, is associated with nodule development, but its specific function remained unknown. In this study, we found that GmNMH7 was specifically expressed in root and nodule and the expression pattern of GmNMH7 was similar to several genes involved in early development of nodule ( GmENOD40-1 , GmENOD40-2, GmNFR1a, GmNFR5a, and GmNIN ) after rhizobia inoculation. The earlier expression peak of GmNMH7 compared to the other genes ( GmENOD40-1 , GmENOD40-2, GmNFR1a, GmNFR5a, and GmNIN ) indicated that the gene is related to the nod factor (NF) signaling pathway and functions at the early development of nodule. Over-expression of GmNMH7 in hairy roots significantly reduced the nodule number and the root length. In the transgenic hairy roots, over-expression of GmNMH7 significantly down-regulated the expression levels of GmENOD40-1 , GmENOD40-2, and GmNFR5α. Moreover, the expression of GmNMH7 could respond to abscisic acid (ABA) and gibberellin (GA 3 ) treatment in the root of Zigongdongdou seedlings. Over-expressing GmNMH7 gene reduced the content of ABA, and increased the content of GA 3 in the positive transgenic hairy roots. Therefore, we concluded that GmNMH7 might participate in the NF signaling pathway and negatively regulate nodulation probably through regulating the content of GA 3 .
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Although MADS-box genes involved in flower and fruit development have been well characterized, the function of MADS-box genes expressed in vegetative structures has yet to be explored. At least seven members of this family are gro...
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Although MADS-box genes involved in flower and fruit development have been well characterized, the function of MADS-box genes expressed in vegetative structures has yet to be explored. At least seven members of this family are grouped in clades of genes that are preferentially expressed in roots of Arabidopsis thaliana (L.) Heynh.. We report here the cloning of the AGL21 MADS-box gene, which belongs to the ANR1 clade, and the mRNA in situ expression patterns of this and two other root MADS-box genes. AGL17 appears to be a lateral root cap marker in the root tip, and towards the elongation zone this gene is expressed in the epidermal cells. AGL21 is highly expressed in lateral root primordia and it has a punctate expression pattern in the primary root meristem. AGL12 also has a punctate expression pattern in the primary root meristem. AGL12 and AGL21 are also expressed in the central cylinder of differentiated roots and both are expressed in developing embryos. This study, combined with previous phylogenetic analyses, indicates that these MADS-box genes may play distinct regulatory roles during root development.
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Gynostemium and ovule development in orchid are unique developmental processes in the plant kingdom. Characterization of C- and D-class MADS-box genes could help reveal the molecular mechanisms underlying gynostemium and ovule dev...
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Gynostemium and ovule development in orchid are unique developmental processes in the plant kingdom. Characterization of C- and D-class MADS-box genes could help reveal the molecular mechanisms underlying gynostemium and ovule development in orchids. In this study, we isolated and characterized a C- and a D-class gene, PeMADS1 and PeMADS7, respectively, from Phalaenopsis equestris. These two genes showed parallel spatial and temporal expression profiles, which suggests their cooperation in gynostemium and ovule development. Furthermore, only PeMADS1 was ectopically expressed in the petals of the gylp (gynostemium-like petal) mutant, whose petals were transformed into gynostemium-like structures. Protein-protein interaction analyses revealed that neither PeMADS1 and PeMADS7 could form a homodimer or a heterodimer. An E-class protein was needed to bridge the interaction between these two proteins. A complementation test revealed that PeMADS1 could rescue the phenotype of the AG mutant. Overexpression of PeMADS7 in Arabidopsis caused typical phenotypes of the D-class gene family. Together, these results indicated that both C-class PeMADS1 and D-class PeMADS7 play important roles in orchid gynostemium and ovule development.
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