Alexandr Goncharov

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Synapses display a stereotyped ultrastructural organization, commonly containing a single electron-dense presynaptic density surrounded by a cluster of synaptic vesicles. The mechanism controlling subsynaptic proportion is not understood. Loss of function in the C. elegans rpm-1 gene, a putative RING finger/E3 ubiquitin ligase, causes disorganized(More)
Axons of adult Caenorhabditis elegans neurons undergo robust regenerative growth after laser axotomy. Here we show that axotomy of PLM sensory neurons triggers axonal calcium waves whose amplitude correlates with the extent of regeneration. Genetic elevation of Ca(2+) or cAMP accelerates formation of a growth cone from the injured axon. Elevated Ca(2+) or(More)
BACKGROUND In many animals, the epidermis is in permanent contact with the environment and represents a first line of defense against pathogens and injury. Infection of the nematode Caenorhabditis elegans by the natural fungal pathogen Drechmeria coniospora induces the expression in the epidermis of antimicrobial peptide (AMP) genes such as nlp-29. Here, we(More)
Cytoplasmic intermediate filaments (cIFs) are thought to provide mechanical strength to vertebrate cells; however, their function in invertebrates has been largely unexplored. The Caenorhabditis elegans genome encodes multiple cIFs. The C. elegans ifb-1 locus encodes two cIF isoforms, IFB-1A and IFB-1B, that differ in their head domains. We show that both(More)
Axons are defined by the presence of presynaptic specializations at specific locations. We show here that loss-of-function mutations in the C. elegans gene syd-1 cause presynaptic specializations to form in the dendritic processes of GABA-expressing motor neurons during initial differentiation. At a later developmental stage, however, syd-1 is not required(More)
Wounding of epidermal layers triggers multiple coordinated responses to damage. We show here that the Caenorhabditis elegans ortholog of the tumor suppressor death-associated protein kinase, dapk-1, acts as a previously undescribed negative regulator of barrier repair and innate immune responses to wounding. Loss of DAPK-1 function results in constitutive(More)
The microtubule (MT) cytoskeleton of a mature axon is maintained in a stabilized steady state, yet after axonal injury it can be transformed into a dynamic structure capable of supporting axon regrowth. Using Caenorhabditis elegans mechanosensory axons and in vivo imaging, we find that, in mature axons, the growth of MTs is restricted in the steady state by(More)
Elongation of the epidermis of the nematode Caenorhabditis elegans involves both actomyosin-mediated changes in lateral epidermal cell shape and body muscle attachment to dorsal and ventral epidermal cells via intermediate-filament/hemidesmosome structures. vab-19 mutants are defective in epidermal elongation and muscle attachment to the epidermis. VAB-19(More)
The presynaptic active zone proteins UNC-13/Munc13s are essential for synaptic vesicle (SV) exocytosis by directly interacting with SV fusion apparatus. An open question is how their association with active zones, hence their position to Ca(2+) entry sites, regulates SV release. The N-termini of major UNC-13/Munc13 isoforms contain a non-calcium binding C2A(More)
Regulation of microtubule dynamics underlies many fundamental cellular mechanisms including cell division, cell motility, and transport. In neurons, microtubules play key roles in cell migration, axon outgrowth, control of axon and synapse growth, and the regulated transport of vesicles and structural components of synapses. Loss of synapse and axon(More)