Genome-wide identification of MADS-box gene family in sacred lotus (Nelumbo nucifera) identifies a SEPALLATA homolog gene involved in floral development

Abstract

Background Sacred lotus (Nelumbo nucifera) is a vital perennial aquatic ornamental plant. Its flower shape determines the horticultural and ornamental values. However, the mechanisms underlying lotus flower development are still elusive. MADS-box transcription factors are crucial in various features of plant development, especially in floral organogenesis and specification. It is still unknown how the MADS-box transcription factors regulate the floral organogenesis in lotus. Results To obtain a comprehensive insight into the functions of MADS-box genes in sacred lotus flower development, we systematically characterized members of this gene family based on the available genome information. A total of 44 MADS-box genes were identified, of which 16 type I and 28 type II genes were categorized based on the phylogenetic analysis. Furthermore, the structure of MADS-box genes and their expressional patterns were also systematically analyzed. Additionally, subcellular localization analysis showed that they are mainly localized in the nucleus, of which a SEPALLATA3 (SEP3) homolog NnMADS14 was proven to be involved in the floral organogenesis. Conclusion These results provide some fundamental information about the MADS-box gene family and their functions, which might be helpful in not only understanding the mechanisms of floral organogenesis but also breeding of high ornamental value cultivars in lotus.

Characterization of Phytohormones and Transcriptomic Profiling of the Female and Male Inflorescence Development in Manchurian Walnut (Juglans mandshurica Maxim.)

“…Floral organ transition and flower development are complex processes regulated by many TFs, especially the MADS-box gene family [ 61 , 62 , 63 ]. At present, multiple MADS-box genes have been identified in many plants, and their functions have also been verified in Medicago sativa [ 64 ], Ipomoea batatas [ 65 ], Adonis amurensis [ 66 ], Nelumbo nucifera [ 67 ] and Phyllostachys edulis [ 68 ]. However, the potential regulatory functions of MADS-box genes during floral organ development in J. mandshurica remain unclear.…”

Studies on Lotus Genomics and the Contribution to Its Breeding

“…The MADS-box TFs are widely involved in plant growth and development. A total of 44 MADS-box genes were identified in lotus, and based on the selected candidates, NnMADS14 (SEPALLATA3 (SEP3) homolog gene) was identified to be related to floral organogenesis in lotus [47]. Lotus possesses distinct types of flower morphology, and the floral organ petaloid phenomenon is universal.…”

Comprehensive Analysis for GRF Transcription Factors in Sacred Lotus (Nelumbo nucifera)

“…N. nucifera is mainly distributed in China, India, Japan, Australia, and Iran [ 23 ]. N. nucifera is domesticated as a food and ornamental crop for its seeds, rhizomes, and flowers [ 24 ]. Since the genomes of N. nucifera were resolved [ 25 , 26 ], a large number of TFs have been isolated and identified, such as MADS-box [ 26 ], WRKY [ 27 ], R2R3-MYB [ 28 ], GRAS [ 29 ], etc.…”