Yelena Bernadskaya

New York University | NYU · Department of Biology

Recent research has elucidated mechanochemical pathways of single cell polarization, but much less is known about collective motility initiation in adhesive cell groups. We used galvanotactic assays of zebrafish keratocyte cell groups, pharmacological perturbations, electric field switches, particle imaging velocimetry and cell tracking to show tha...

Physiological and pathological morphogenetic events involve a wide array of collective movements, suggesting that multicellular arrangements confer biochemical and biomechanical properties contributing to tissue scale organization. The Ciona cardiopharyngeal progenitors provide the simplest model of collective cell migration, with cohesive bilatera...

Physiological and pathological morphogenetic events involve a wide array of collective movements, suggesting that these multicellular arrangements confer biochemical and biomechanical properties that contribute to tissue scale organization. The cardiopharyngeal progenitors of the tunicate Ciona provide the simplest possible model of collective cell...

Integrated analyses of regulated effector genes, cellular processes, and extrinsic signals are required to understand how transcriptional networks coordinate fate specification and cell behavior during embryogenesis. Ciona cardiopharyngeal progenitors, the trunk ventral cells (TVCs), polarize as leader and trailer cells that migrate between the ven...

Actin is an integral component of epithelial apical junctions, yet the interactions of branched actin regulators with apical junction components are still not clear. Biochemical data have shown that α-catenin inhibits Arp2/3-dependent branched actin. These results suggested that branched actin is only needed at earliest stages of apical junction de...

Integrated analyses of regulated effector genes, cellular processes, and extrinsic signals are required to understand how transcriptional networks coordinate fate specification and cell behavior during embryogenesis. Migratory pairs of cardiac progenitors in the tunicate Ciona provide the simplest model of collective migration in chordate embryos....

Tissue-specific transcription regulators emerged as key developmental control genes, which operate in the context of complex gene regulatory networks (GRNs) to coordinate progressive cell fate specification and tissue morphogenesis. We discuss how GRNs control the individual cell behaviors underlying complex morphogenetic events. Cell behaviors cla...

Collectively migrating cells maintain group polarity and interpret external cues to reach their destination. The cardiogenic progenitors (also known as trunk ventral cells, TVCs) of the ascidian Ciona intestinalis provide a simple chordate model with which to study collective migration. Bilateral pairs of associated TVCs undergo a stereotyped polar...

UNC-40/DCC, SAX-3/Robo and VAB-1/Eph are required for F-actin regulation during embryonic morphogenesis. Live C. elegans embryos of the indicated genotypes are shown during epidermal morphogenesis with F-actin marked by an epidermis-specific transgene, plin-26::VAB-10 ABD::GFP (mcIs5). The movies, made at 23°C begin at the onset of epidermal migrat...

Effects of UNC-40/DCC, SAX-3/Robo or VAB-1/Eph loss on the Leading Cells during morphogenesis. The two Leading Cells from an embryo of each genotype are highlighted to show the leading edge dynamics and ventral to dorsal F-actin enrichment in these cells during morphogenesis (same time points as Movie 1). (MOV)

Dynamics of protrusion turnover in wild type and morphogenesis defective mutants. Protrusion formation and turnover is illustrated using the plin-26::VAB-10 ABD::GFP transgene. The cells at the top of the frame at the beginning of the movies include the Leading Cells in the ventral row of epidermal cells that migrate ventrally (down) in wild type....

Many cells in a developing embryo, including neurons and their axons and growth cones, must integrate multiple guidance cues to undergo directed growth and migration. The UNC-6/netrin, SLT-1/slit, and VAB-2/Ephrin guidance cues, and their receptors, UNC-40/DCC, SAX-3/Robo, and VAB-1/Eph, are known to be major regulators of cellular growth and migra...

It has been proposed that Arp2/3, which promotes nucleation of branched actin, is needed for epithelial junction initiation but is less important as junctions mature. We focus here on how Arp2/3 contributes to the Caenorhabditis elegans intestinal epithelium and find important roles for Arp2/3 in the maturation and maintenance of junctions in embry...

The WAVE/SCAR complex promotes actin nucleation through the Arp2/3 complex, in response to Rac signaling. We show that loss of WVE-1/GEX-1, the only C. elegans WAVE/SCAR homolog, by genetic mutation or by RNAi, has the same phenotype as loss of GEX-2/Sra1/p140/PIR121, GEX-3/NAP1/HEM2/KETTE, or ABI-1/ABI, the three other components of the C. elegans...