High impact information on SEP1

• In addition, in situ RNA hybridization experiments with AGL1 and AGL2 show that their mRNAs are detected in some floral organs but not in others [1].
• In Arabidopsis, APETALA1, PISTILLATA, APETALA3 and SEPALLATA interact to form multimeric protein complexes required to specify petal identity [2].
• We isolated and sequenced three genomic regions from diploid Cleome spinosa (Cleomaceae) that are each homoeologous to a duplicated region shared between At3 and At5, centered on the paralogs of SEPALLATA (SEP) and CONSTANS (CO) [3].
• Toward the analysis of the petunia MADS box gene family by reverse and forward transposon insertion mutagenesis approaches: B, C, and D floral organ identity functions require SEPALLATA-like MADS box genes in petunia [4].
• Here, we describe results from DNA binding studies of AGL1 and AGL2 (for AGAMOUS-like), two Arabidopsis MADS domain proteins that are preferentially expressed in flowers [5].

Biological context of SEP1

• Although sep4 single mutants display a phenotype similar to that of wild-type plants, we find that floral organs are converted into leaf-like organs in sep1 sep2 sep3 sep4 quadruple mutants, indicating the involvement of all four SEP genes in the development of sepals [6].
• Phylogenetic analyses of SEP sequences show that several gene duplications occurred during the evolution of this subfamily, providing potential opportunities for functional divergence [7].
• We also found that AGL2 binds to DNA in vitro as a dimer and determined the region of AGL2 that is sufficient for DNA binding and dimerization [5].
• AGL2 is one of several Arabidopsis floral MADS-box genes that were isolated based on sequence similarity to the homeotic gene AGAMOUS [8].
• Sequence based analyses indicate that PTM3 (Populus tremuloides MADS-box 3), and a duplicate gene PTM4, are related to the SEPALLATA1-and 2-class of MADS-box genes [9].

Associations of SEP1 with chemical compounds

• In this study, a MADS box gene, TaMADS1, was isolated and characterized from wheat (Triticum aestivum L.). The analysis of amino acid sequences and phylogenetic tree suggested that the TaMADS1 gene might be a SEPALLATA (SEP)-like gene [10].

Regulatory relationships of SEP1

• We show that the presence of SEPALLATA proteins is needed to activate the AG downstream gene SHATTERPROOF2, and that SEPALLATA4 alone does not provide with enough SEPALLATA activity for the complex to be functional [11].

Other interactions of SEP1

• The timing of the first SEP duplication approximately coincides with duplications in the DEFICIENS/GLOBOSA and AGAMOUS MADS-box subfamilies, which may have resulted from either a proposed genome-wide duplication in the ancestor of extant angiosperms or multiple independent duplication events [7].
• The first duplication occurred prior to the origin of the extant angiosperms, resulting in the AGL2/3/4 and AGL9 clades [7].
• The transcripts of Sep1 and Sep2 were present under low light conditions, but their level increased 4- to 10-fold during illumination of plants with high-intensity light [12].
• Wheat AP1 and AGLG1 genes were similar to Arabidopsis meristem identity genes AP1 and AGL2, respectively [13].
• Although these phenomena have not been directly observed in Arabidopsis, the integrative role of the SEPALLATA function in reproductive meristem development may be general for all flowering plants [14].

Analytical, diagnostic and therapeutic context of SEP1

• To investigate its possible role in flower development, we have characterized in detail the expression pattern of AGL2 in both wild-type and mutant flowers using RNA in situ hybridization [8].
• Sequence analysis revealed that NtMADS1 encodes a putative MADS-box protein homologous to the AGL2 with 68.4% identity and 82% similarity in amino acids [15].

References