A perspective on the molecular mechanism in the control of organ internal (IN) asymmetry during petal development

Abstract

Floral zygomorphy (monosymmetry) is a key innovation in flowering plants and is related to the coevolution of plants and their animal pollinators. The molecular basis underlying floral zygomorphy has been analyzed, and two regulatory pathways have been identified: one determines the dorsoventral (DV) asymmetry along the floral plan, and the other controls organ internal (IN) asymmetry during petal development. While strides have been made to understand the molecular mechanism controlling DV asymmetry, which mainly involves an interplay between TCP and MYB transcription factors, the molecular pathway regulating IN asymmetry remains largely unknown. In this review, we discuss what is known about regulators and the molecular pathway regulating IN asymmetry. Our analysis revealed that the regulation of IN asymmetry occurs at the cellular, tissue, and organ genesis levels during petal development and that the regulatory mechanism is likely integrated into different developmental paths, such as floral and root nodule development. Although the molecular regulation of IN asymmetry is not be a linear path, a key hub for the regulatory network could be vascular patterning during petal organogenesis.

Innovations in functional genomics and molecular breeding of pea: exploring advances and opportunities

“…The flower, a reproductive organ in angiosperms, develops through a complex process involving the coordinated action of numerous genes. Peas, as members of the Faboideae subfamily, are characterized by their distinctive papilionaceous flowers comprised of five petals: an upward-facing standard, two lateral wings, and two keels that form a boat-like shape (Yu et al 2022 ). Flower development directly impacts a plant’s pollination and fruiting capabilities, ultimately influencing yield (Dohzono and Yokoyama 2010 ).…”

“…In Papilionoideae legumes, zygomorphic flowers are characterized by a distinct corolla with three petal types, displaying both dorsoventral (DV) and internal (IN) asymmetry. As a result, the symmetry of pea flowers has become a focal point in the study of pea floral organ development (Yu et al 2022 ). The K locus and LOBED STANDARD 1 ( LST1 ) locus encode CYC-like TCP proteins, which act as DV regulators, controlling lateral and dorsal identities, respectively.…”