Entries by Jesus Leon

A spatiotemporal molecular switch governs plant asymmetric cell division (Nature Plants)

In multicellular organisms, stem cells produce various cell types through asymmetric cell division (ACD), which is achieved is through polarization of cell-fate determinant proteins in the ACD progenitor cells. In Arabidopsis stomatal development, an ACD progenitor cell, the meristemoid mother cell (MMC), produces daughter cells with different cell-fates: a meristemoid and a stomatal lineage ground […]

LEAFY is a pioneer transcription factor and licenses cell reprogramming to floral fate (Nature Comms)

Master transcription factors (TFs) can activate specific genetic programs to reprogram cellular fate in the context of open chromatin. A special class of these proteins known as pioneer TFs are defined by their ability to trigger cell fate reprogramming by binding their cognate cis motifs in a nucleosome context both in vitro and in vivo, […]

Molecular mechanism of cytokinin-activated cell division in Arabidopsis (Science)

Proper organogenesis depends on the precise control of cell proliferation and differentiation. Cytokinin and auxin have emerged as key regulators of both these processes, where cytokinin promotes proliferation and synergistically with auxin fine-tunes the proliferation and differentiation rate. Years of research and evidence have implicated cytokinin as a central regulator of stem cell proliferation in […]

NO GAMETOPHORES 2 is a novel regulator of the 2D to 3D growth transition in the moss Physcomitrella patens (Curr. Biol.)

Three-dimensional (3D) growth was an essential evolutionary innovation that allowed the radiation and diversification of land plants. In most land plants the transition from two-dimensional (2D) to 3D growth takes place during embryo development and its disruption results in lethality, however, the disruption of the 2D to 3D growth in Physcomitrella (Physcomitrium) patens is not […]

CLAVATA signaling ensures reproductive development in plants across thermal environments (Curr. Biol.)

Plant reproduction and development requires robust signaling pathways that integrate environmental queues such as temperature. In Arabidopsis, the formation of flower primordia from the inflorescence meristem (IM) depends on the proliferation/ differentiation balance and is regulated by auxin and the conserved CLAVATA3 (CLV3) signaling pathway. CLV3 acts through many receptors to negatively regulate the WUSCHEL […]

Conserved transcriptional programs underpin organogenesis and reproduction in land plants (bioRxiv)

Land plant evolution accompanied a plethora of evolutionary novelties such as cells that compose complex organs (e.g., stems, leaves, roots) and male/female gametophytes. The identity and conservation of the transcriptional programs underlying organogenesis and reproductive development across land plants remains poorly explored. Julca et al., generated expression atlases of several organs and gametes for 10 […]

Review: Gemma cup and gemma development in Marchantia polymorpha (New Phytol.)

Plants have the astounding capacity to generate new plants derived from specialized organs (i.e., roots, leaves, and stems). This capacity, known as vegetative propagation, is used by horticulturists and farmers to propagate clonal varieties. This form of reproduction is fueled by the ability to regenerate and proliferate meristems from differentiated tissue. The liverwort model Marchantia […]

Development and cell cycle dynamics of the root apical meristem in the fern Ceratopteris richardii (bioRxiv)

Roots are essential organs for nutrient and water uptake and have been extensively investigated in angiosperms. Many studies suggest that roots originated through convergent evolution in vascular plants, a clade that includes seed plants and ferns. Besides Arabidopsis and crops, little is known about root development in extant early-divergent tracheophytes such as ferns, which represent […]

Review. Roles of plant retinoblastoma protein: cell cycle and beyond (EMBO J.)

The cell cycle is at the heart of processes such as cell division, fate acquisition and cell cycle exit towards differentiation. Decades of cell cycle research in animals and yeast have outlined the main components that control the cycle’s transitions, such as cyclins, cyclin-dependent kinases, E2F transcription factors and the Retinoblastoma (RB1) tumor suppressor. Mostly […]