Publications by authors named "Bhagaban Mallik"

Intracellular membrane tubules play a crucial role in diverse cellular processes, and their regulation is facilitated by Bin-Amphiphysin-Rvs (BAR) domain-containing proteins. This study investigates the roles of ICA69 (dICA69) (an N-BAR protein) and CIP4 (dCIP4) (an F-BAR protein), focusing on their impact on membrane tubule organization. In contrast to the prevailing models of BAR-domain protein function, we observed colocalization of endogenous dICA69 with dCIP4-induced tubules, indicating their potential recruitment for tubule formation and maintenance.

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Membrane protrusions are fundamental to cellular functions like migration, adhesion, and communication and depend upon dynamic reorganization of the cytoskeleton. GAP-dependent GTP hydrolysis of Arf proteins regulates actin-dependent membrane remodeling. Here, we show that dAsap regulates membrane protrusions in S2R+ cells by a mechanism that critically relies on its ArfGAP domain and relocalization of actin regulators, SCAR, and Ena.

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A range of experiments suggests that creatine, a molecule known for recycling ATP in muscle and brain tissue, may also function as a neurotransmitter in the central nervous system.

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Mutation of the gene or pharmacological agents targeting it are commonly used to assess homeostatic synaptic function at the larval neuromuscular junction (NMJ). The commonly used mutation, , is a null allele created by a large and imprecise excision of a P-element which affects and multiple upstream genes. Here we mapped the exact bounds of the allele, refined a multiplex PCR strategy for positive identification of in homozygous or heterozygous backgrounds, and sequenced and characterized three new CRISPR-generated mutants.

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Several proteins contain signaling domains that can regulate the cell membrane dynamics as well as the underlying cytoskeleton. Among these, Bin-Amphiphysin-Rvs (BAR) domain-containing proteins, with their membrane deforming properties, have emerged as the key players in regulating neuronal morphology and inducing neuronal signaling that can modulate synaptic architecture. While the biochemical and structural basis of membrane deformation by the BAR-domain proteins has been extensively studied, the in vivo contexts in which these proteins function remain to be elucidated.

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To identify conserved components of synapse function that are also associated with human diseases, we conducted a genetic screen. We used the neuromuscular junction (NMJ) as a model. We employed RNA interference (RNAi) on selected targets and assayed synapse function and plasticity by electrophysiology.

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The endoplasmic reticulum (ER) constitutes about half of the total membrane of a eukaryotic cell, and defects in the ER have been shown to be linked with a variety of diseases. To investigate these underlying mechanisms in detail, the specific labelling of the ER for high-resolution long-term live-imaging can serve as an important tool. Here, we report the identification of a stimulated emission depletion (STED) microscopy-compatible BODIPY derivative (NH2-BODIPY) to selectively image the ER.

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A small molecule, perylene bisimide imidazolyl derivative (PBI-ID), has been identified and developed as a specific marker for labelling multifunctional fat bodies in various organisms, including Drosophila and mammalian adipocytes. Interestingly, PBI-ID neither labels the plasma membranes nor cell nuclei by trapping into it. A remarkable feature of unbound PBI-ID is diminished fluorescence, which reduces the background emission noise, while contrasting the bound state effectively.

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Accumulation of toxic proteins in neurons has been linked with the onset of neurodegenerative diseases, which in many cases are characterized by altered neuronal function and synapse loss. Molecular chaperones help protein folding and the resolubilization of unfolded proteins, thereby reducing the protein aggregation stress. While most of the chaperones are expressed in neurons, their functional relevance remains largely unknown.

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The mechanisms underlying synaptic differentiation, which involves neuronal membrane and cytoskeletal remodeling, are not completely understood. We performed a targeted RNAi-mediated screen of BAR-domain proteins and identified islet cell autoantigen 69 kDa (ICA69) as one of the key regulators of morphological differentiation of the larval neuromuscular junction (NMJ). We show that ICA69 colocalizes with α-Spectrin at the NMJ.

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