A5072644672- Marine Invertebrate Physiology and Ecology
- Protist diversity and phylogeny
- Cellular transport and secretion
- Photoreceptor and optogenetics research
- Marine Ecology and Invasive Species
- Microbial Community Ecology and Physiology
- Plant and Biological Electrophysiology Studies
- Connexins and lens biology
- Lipid Membrane Structure and Behavior
- Retinal Development and Disorders
- Microtubule and mitosis dynamics
- Coral and Marine Ecosystems Studies
- Neuroscience and Neuropharmacology Research
- Planarian Biology and Electrostimulation
- Marine Sponges and Natural Products
- Protein Kinase Regulation and GTPase Signaling
- Marine Toxins and Detection Methods
- Aquaculture disease management and microbiota
- Genomics and Phylogenetic Studies
- Genetics, Aging, and Longevity in Model Organisms
- Developmental Biology and Gene Regulation
- Marine Biology and Ecology Research
- Lysosomal Storage Disorders Research
- Animal Vocal Communication and Behavior
- 14-3-3 protein interactions
University of Bergen
2018-2025
Marine Biological Association of the United Kingdom
2015-2024
Karolinska Institutet
2023
University of Zurich
2023
University of California, Berkeley
2013-2016
Howard Hughes Medical Institute
2014-2016
Max Planck Institute for Biophysical Chemistry
2008-2014
Max Planck Society
2011
Southeast Asian Fisheries Development Center
1986
The evolutionary origin of metazoan cell types such as neurons and muscles is not known. Using whole-body single-cell RNA sequencing in a sponge, an animal without nervous system musculature, we identified 18 distinct types. These include nitric oxide–sensitive contractile pinacocytes, amoeboid phagocytes, secretory neuroid cells that reside close contact with digestive choanocytes express scaffolding receptor proteins. Visualizing by correlative x-ray electron microscopy revealed vesicles...
A fundamental breakthrough in neurobiology has been the formulation of neuron doctrine by Santiago Ramón y Cajal, which stated that nervous system is composed discrete cells. Electron microscopy later confirmed and allowed identification synaptic connections. In this work, we used volume electron three-dimensional reconstructions to characterize nerve net a ctenophore, marine invertebrate belongs one earliest-branching animal lineages. We found neurons subepithelial have continuous plasma...
Activation triggers the exchange of subunits in Ca2+/calmodulin-dependent protein kinase II (CaMKII), an oligomeric enzyme that is critical for learning, memory, and cardiac function. The mechanism by which subunit occurs remains elusive. We show human CaMKII holoenzyme exists dodecameric tetradecameric forms, calmodulin (CaM)-binding element can bind to hub destabilize it release dimers. structures from two distantly diverged organisms suggest CaM-binding activated acts as a wedge docking...
Although collar cells are conserved across animals and their closest relatives, the choanoflagellates, little is known about ancestry, subcellular architecture, or how they differentiate. The choanoflagellate Salpingoeca rosetta expresses genes necessary for animal development can alternate between unicellular multicellular states, making it a powerful model investigating origin of multicellularity mechanisms underlying cell differentiation. To compare architecture solitary in S. with that...
Filopodia are fine actin-based cellular projections used for both environmental sensing and cell motility, they essential organelles metazoan cells. In this study, we reconstruct the origin of filopodia microvilli. We first report on evolutionary assembly filopodial molecular toolkit show that homologs many components, including fascin myosin X, were already present in unicellular or colonial progenitors metazoans. Furthermore, find actin crosslinking protein localizes to filopodia-like...
SNARE protein-driven secretion of neurotransmitters from synaptic vesicles is at the center neuronal communication. In absence cytosolic protein Munc18-1, comes to a halt. Although it believed that Munc18-1 orchestrates complexes, its mode action still matter debate. particular, has been challenging clarify role tight Munc18/syntaxin 1 complex, because this interaction interferes strongly with syntaxin's ability form complex. two regions syntaxin, N-peptide and remainder in closed...
In neurons, soluble N -ethylmaleimide–sensitive factor attachment receptor (SNARE) proteins drive the fusion of synaptic vesicles to plasma membrane through formation a four-helix SNARE complex. Members Sec1/Munc18 protein family regulate interactions with syntaxin proteins. The neuronal Munc18a interacts closed conformation syntaxin1a (Syx1a) and an assembled complex containing Syx1a in open conformation. N-peptide (amino acids 1–24) has been implicated transition Munc18a-bound complex, but...
Reconstructing the evolution and ancestral functions of synaptic proteins promises to shed light on how neurons first evolved. The postsynaptic density (PSD) protein Homer scaffolds membrane receptors regulates Ca(2+) signaling in diverse metazoan cell types (including muscle cells), yet its ancestry core are poorly understood. We find that domain organization essential biochemical properties proteins, including their ability tetramerize, conserved choanoflagellate Salpingoeca rosetta, one...
Abstract The evolutionary origin of metazoan cell types such as neurons, muscles, digestive, and immune cells, remains unsolved. Using whole-body single-cell RNA sequencing in a sponge, an animal without nervous system musculature, we identify 18 distinct comprising four major families. This includes nitric-oxide sensitive contractile digestive cells active macropinocytosis, family amoeboid-neuroid involved innate immunity. We uncover ‘presynaptic’ genes type, ‘postsynaptic’ choanocytes,...
The transition from simple to complex multicellularity involves division of labor and specialization cell types. In animals, sensory-motor systems are primarily built around specialized cells muscles neurons, though the evolutionary origins these their integration remain unclear. Here, investigate sensory-behavior coupling in closest relatives we established a line choanoflagellate, Salpingoeca rosetta, which stably expresses calcium indicator RGECO1. Using this, identify previously unknown...
Significance Every vesicle fusion reaction is driven by soluble N-ethylmaleimide–sensitive factor attachment protein receptor (SNARE) proteins that zipper into tight complexes between membranes. Members of the Sec1/Munc18 (SM) family tightly regulate this process through interactions with a member syntaxin SNARE subfamily. However, seemingly different interaction modes have been found for SM and syntaxins. Here we show ER–Golgi Sly1 interacts not only N-peptide Sed5, as previously thought,...
The "ribbon," a structural arrangement in which Golgi stacks connect to each other, is considered be restricted vertebrate cells. Although ribbon disruption linked various human pathologies, its functional role cellular processes remains unclear. In this study, we investigate the evolutionary origin of ribbon. We observe ribbon-like architecture cells several metazoan taxa suggesting early emergence animal evolution predating appearance vertebrates. Supported by AlphaFold2 modeling, propose...
ABSTRACT As the closest living relatives of animals, choanoflagellates offer insights into ancestry animal cell physiology. Here, we report isolation and characterization a colonial choanoflagellate from Mono Lake, California. The forms large spherical colonies that are an order magnitude larger than those formed by closely related Salpingoeca rosetta . In cultures maintained in laboratory, lumen colony is filled with branched network extracellular matrix colonized bacteria, including...
Neurosecretory vesicles are highly specialized trafficking organelles that store neurotransmitters released at presynaptic nerve endings and are, therefore, important for animal cell–cell signalling. Despite considerable anatomical functional diversity of neurons in animals, the protein composition neurosecretory bilaterians appears to be similar. This similarity points towards a common evolutionary origin. Moreover, many putative homologues key vesicle proteins predate origin first neurons,...
Neurons, especially when coupled with muscles, allow animals to interact and navigate through their environment in ways unique life on earth. Found all major animal lineages except sponges placozoans, nervous systems range widely organization complexity, neurons possibly representing the most diverse cell-type. This diversity has led much debate over evolutionary origin of as well synapses, which for directed transmission information. The broad phylogenetic distribution presence many...
Abstract Chromatin regulation is a key process in development but its contribution to the evolution of animals largely unexplored. regulated by diverse set proteins, which themselves are tightly cell/tissue-specific manner. Using cnidarian Nematostella vectensis as basal metazoan model, we explore function one such chromatin regulator, Lysine specific demethylase 1 (Lsd1). We generated an endogenously tagged allele and show that NvLsd1 expression developmentally higher differentiated neural...