The Aquilegia FRUITFULL‐like genes play key roles in leaf morphogenesis and inflorescence development. (7th March 2013)

• Record Type: Journal Article
• Authors: Pabón‐Mora, Natalia; Sharma, Bharti; Holappa, Lynn D.; Kramer, Elena M.; Litt, Amy
• Is Part Of: Plant journal. Volume 74:Number 2(2013:Apr.)
• Page Start: 197
• Page End: 212
• Publication Date: 2013-03-07
• Subjects: Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.12113
• Languages: English
• ISSNs: 0960-7412

Abstract

<abstract abstract-type="main" id="tpj12113-abs-0001"> <title>Summary</title> <p>The <italic>APETALA1</italic>/<italic>FRUITFULL</italic> (<italic>AP1</italic>/<italic>FUL</italic>) MADS box transcription factors are best known for the role of <italic>AP1</italic> in Arabidopsis sepal and petal identity, the canonical A function of the ABC model of flower development. However, this gene lineage underwent multiple duplication events during angiosperm evolution, providing different taxa with unique gene complements. One such duplication correlates with the origin of the core eudicots, and produced the <italic>euAP1</italic> and <italic>euFUL</italic> clades. Together, <italic>euAP1</italic> and <italic>euFUL</italic> genes function in proper floral meristem identity and repression of axillary meristem growth. Independently, <italic>euAP1</italic> genes function in floral meristem and sepal identity, whereas <italic>euFUL</italic> genes control phase transition, cauline leaf growth and fruit development. To investigate the impact of the core eudicot duplication on the functional diversification of this gene lineage, we studied the role of pre‐duplication <italic>FUL‐like</italic> genes in columbine (<italic>Aquilegia coerulea</italic>). Our results show that <italic>AqcFL1</italic> genes are broadly expressed in vegetative and reproductive meristems, leaves and flowers. Virus‐induced gene silencing of the loci results in plants with increased branching, shorter inflorescences with fewer flowers, and dramatic changes in leaf shape and complexity. However, <italic>aqcfl1</italic> plants have normal flowers and fruits. Our results show that, in contrast to characterized <italic>AP1</italic>/<italic>FUL</italic> genes, the <italic>AqcFL1</italic> loci are either genetically redundant or have been decoupled from the floral genetic program, and play a major role in leaf morphogenesis. We analyze the results in the context of the core eudicot duplication, and discuss the implications of our findings in terms of the genetic regulation of leaf morphogenesis in <italic>Aquilegia</italic> and other flowering plants.</p> </abstract>