Hemolysin Coregulated Protein (HCP) from Interacts with the Host Cell Actin Cytoskeleton.

(), the etiological agent of cholera, employs various virulence factors to adapt and thrive within both aquatic and human host environments. Among these factors, the type VI secretion system (T6SS) stands out as one of the crucial determinants of its pathogenicity. Valine glycine repeat protein G1 (VgrG1) and hemolysin coregulated protein (HCP) are considered major effector molecules of T6SS.

Biotinylated Theranostic Amphiphilic Polyurethane for Targeted Drug Delivery.

In the area of drug delivery aided by stimuli-responsive polymers, the biodegradability of nanocarriers is one of the major challenges that needs to be addressed with the utmost sincerity. Herein, a hydrogen sulfide (HS) responsive hydrophobic dansyl-based trigger molecule is custom designed and successfully incorporated into the water-soluble polyurethane backbone, which is made of esterase enzyme susceptible urethane bonds. The amphiphilic polyurethanes, (x = 2 and 3) with a biotin chain end, formed self-assembled nanoaggregates.

Role of Macrophage PIST Protein in Regulating Infection.

PDZ protein interacting specifically with Tc10 or PIST is a mammalian trans-Golgi resident protein that regulates subcellular sorting of plasma membrane receptors. PIST has recently emerged as a key player in regulating viral pathogenesis. Nevertheless, the involvement of PIST in parasitic infections remains unexplored.

Probing the ligand binding specificity of FNBP4 WW domains and interaction with FH1 domain of FMN1.

Formins are a group of actin-binding proteins that mediate nascent actin filament polymerization, filament elongation, and barbed end-capping function, thereby regulating different cellular and developmental processes. Developmental processes like vertebrate gastrulation, neural growth cone dynamics, and limb development require formins functioning in a regulated manner. Formin-binding proteins like Rho GTPase regulate the activation of auto-inhibited conformation of diaphanous formins.

Zwitterionic Polysulfobetaine Inhibits Cancer Cell Migration Owing to Actin Cytoskeleton Dynamics.

Cell migration is an essential dynamic process for most living cells, mainly driven by the reorganization of actin cytoskeleton. To control actin dynamics, a molecular architecture that can serve as a nucleator has been designed by polymerizing sulfobetaine methacrylate. The synthesized zwitterionic polymer, poly(sulfobetaine methacrylate) (), effectively nucleates the polymerization process of G-actin and substantially accelerates the rate of polymerization.

Cholate-conjugated cationic polymers for regulation of actin dynamics.

Cytoskeletal movement is a compulsory necessity for proper cell functioning and is largely controlled by actin filament dynamics. The actin dynamics can be fine-tuned by various natural and artificial materials including cationic proteins, polymers, liposomes, and lipids, although most of the synthetic substrates have toxicity issues. Herein, we show actin nucleation and stabilization with a synthetic family of cholic acid (CA)-conjugated cationic macromolecules.

Unravelling the Biology of EhActo as the First Cofilin From .

Actin-depolymerising factors (ADF) are a known family of proteins that regulate actin dynamics. Actin regulation is critical for primitive eukaryotes since it drives their key cellular processes. , a protist human pathogen harbours eleven proteins within this family, however, with no actin depolymerising protein reported to date.

Role of actin cytoskeleton in the organization and function of ionotropic glutamate receptors.

Neural networks with precise connection are compulsory for learning and memory. Various cellular events occur during the genesis of dendritic spines to their maturation, synapse formation, stabilization of the synapse, and proper signal transmission. The cortical actin cytoskeleton and its multiple regulatory proteins are crucial for the above cellular events.

Coupling of dynamic microtubules to F-actin by Fmn2 regulates chemotaxis of neuronal growth cones.

Dynamic co-regulation of the actin and microtubule subsystems enables the highly precise and adaptive remodelling of the cytoskeleton necessary for critical cellular processes, such as axonal pathfinding. The modes and mediators of this interpolymer crosstalk, however, are inadequately understood. We identify Fmn2, a non-diaphanous-related formin associated with cognitive disabilities, as a novel regulator of cooperative actin-microtubule remodelling in growth cones of both chick and zebrafish neurons.

Molecular identification of bio-fluids in gas phase using infrared spectroscopy.

Bio-fluids are the source of a large number of metabolites. Identification and quantification of them can be an efficient step for understanding the internal chemistry of the body as well as for developing objective diagnostics of diseases. Several techniques have been developed so far; however, their metabolite identification and/or quantification are not reliable enough for acceptance by clinicians.

EhC2B, a C2 domain-containing protein, promotes erythrophagocytosis in Entamoeba histolytica via actin nucleation.

Remodelling of the actin cytoskeleton in response to external stimuli is obligatory for many cellular processes in the amoebic cell. A rapid and local rearrangement of the actin cytoskeleton is required for the development of the cellular protrusions during phagocytosis, trogocytosis, migration, and invasion. Here, we demonstrated that EhC2B, a C2 domain-containing protein, is an actin modulator.

Presence of actin binding motif in VgrG-1 toxin of Vibrio cholerae reveals the molecular mechanism of actin cross-linking.

Type VI secretion systems (T6SS) plays a crucial role in Vibrio cholerae mediated pathogenicity. Tip of T6SS is homologous to gp27/gp5 complex or tail spike of T4 bacteriophage. VgrG-1 of V.

Non diaphanous formin delphilin acts as a barbed end capping protein.

Formins are multi domain proteins present ubiquitously in all eukaryotes from lower fungi to higher vertebrates. Formins are characterized by the presence of formin homology domain-2 (FH2) and formin homology domain-1 (FH1). There are fifteen different formins present in mouse and human.

Side-chain amino acid based cationic polymer induced actin polymerization.

Actin filament dynamics is important for proper cellular functions and is controlled by hundreds of actin binding proteins inside the cells. There are several natural and synthetic compounds that are able to bind actin and alter the actin filament dynamics. Since the actin dynamics changes due to nonspecific electrostatic interactions between negatively charged actin and positively charged proteins, and natural or synthetic compounds, herein we report the synthesis of poly(tert-butyl carbamate (Boc)-l-alanine methacryloyloxyethyl ester) (P(Boc-Ala-HEMA)) homopolymer in a controlled fashion by the reversible addition-fragmentation chain transfer (RAFT) polymerization.

Evaluation of Models of Parkinson's Disease.

Parkinson's disease is one of the most common neurodegenerative diseases. Animal models have contributed a large part to our understanding and therapeutics developed for treatment of PD. There are several more exhaustive reviews of literature that provide the initiated insights into the specific models; however a novel synthesis of the basic advantages and disadvantages of different models is much needed.

Expression of multiple formins in adult tissues and during developmental stages of mouse brain.

Formins are highly conserved heterogeneous family of proteins with several isoforms having significant contribution in multiple cellular functions. Formins play crucial role in remodelling of actin cytoskeleton and thus play important role in cell motility. Formins are also involved in many cellular activities like determining cell polarity, cytokinesis and morphogenesis.

EhCoactosin stabilizes actin filaments in the protist parasite Entamoeba histolytica.

Entamoeba histolytica is a protist parasite that is the causative agent of amoebiasis, and is a highly motile organism. The motility is essential for its survival and pathogenesis, and a dynamic actin cytoskeleton is required for this process. EhCoactosin, an actin-binding protein of the ADF/cofilin family, participates in actin dynamics, and here we report our studies of this protein using both structural and functional approaches.

Significant association of the dupA gene of Helicobacter pylori with duodenal ulcer development in a South-east Indian population.

A novel virulence factor, duodenal ulcer-promoting gene A (dupA), in Helicobacter pylori has been found to be associated with disease in certain populations but not in others. This study analysed a South-east Indian population as part of the debate about the relevance of dupA for the prediction of clinical outcomes. A total of 140 H.

Structure and activity of full-length formin mDia1.

Formins are a conserved family of actin assembly-promoting factors with essential and diverse biological roles. Most of our biochemical understanding of formin effects on actin dynamics is derived from studies using formin fragments. In addition, all structural information on formins has been limited to fragments.

Biodegradation and in vitro biocompatibility of polyperoxides: alternating co-polymers of vinyl monomers and molecular oxygen.

Vinyl polyperoxides, alternating co-polymers of vinyl monomers and molecular oxygen, are a small but important class of polymers with unique properties, such as highly exothermic degradation in contrast to common polymers, which generally show endothermic degradation. Enzymatic degradation and in vitro biocompatibility have been studied for the vinyl polyperoxides polystyrene peroxide (PSP), poly(α- methylstyrene) peroxide (PAMSP) and poly(methyl methacrylate) peroxide (PMMAP). Enzymatic degradation of polyperoxides has been carried out using horseradish peroxidase enzyme at room temperature.

The formin DAD domain plays dual roles in autoinhibition and actin nucleation.

Formins are a large family of actin assembly-promoting proteins with many important biological roles. However, it has remained unclear how formins nucleate actin polymerization. All other nucleators are known to recruit actin monomers as a central part of their mechanisms.

Isolation and characterization of cytoplasmic cofilin-actin rods.

Cofilin-actin bundles (rods), which form in axons and dendrites of stressed neurons, lead to synaptic dysfunction and may mediate cognitive deficits in dementias. Rods form abundantly in the cytoplasm of non-neuronal cells in response to many treatments that induce rods in neurons. Rods in cell lysates are not stable in detergents or with added calcium.

Structure of the FH2 domain of Daam1: implications for formin regulation of actin assembly.

Daam1 (dishevelled-associated activator of morphogenesis-1) is a diaphanous-related formin first studied as a novel dishevelled binding protein and shown to be crucial for the planar cell polarity (PCP) pathway in Xenopus. Daam1, like other formins, directs nucleation and elongation of new actin filaments using its conserved formin-homology-2 (FH2) domain. Here we report the crystal structure of a large C-terminal fragment of human Daam1 containing the FH2 domain.

Formin proteins: purification and measurement of effects on actin assembly.

We describe methods for expressing and isolating formin proteins from a wide range of species and comparing quantitatively their effects on actin assembly. We first developed these procedures for purification of S. cerevisiae formins Bni1 and Bnr1 but have extended them to mammalian formins, including mouse mDia1 and mDia2 and human Daam1.

Interplay between components of a novel LIM kinase-slingshot phosphatase complex regulates cofilin.

Slingshot (SSH) phosphatases and LIM kinases (LIMK) regulate actin dynamics via a reversible phosphorylation (inactivation) of serine 3 in actin-depolymerizing factor (ADF) and cofilin. Here we demonstrate that a multi-protein complex consisting of SSH-1L, LIMK1, actin, and the scaffolding protein, 14-3-3zeta, is involved, along with the kinase, PAK4, in the regulation of ADF/cofilin activity. Endogenous LIMK1 and SSH-1L interact in vitro and co-localize in vivo, and this interaction results in dephosphorylation and downregulation of LIMK1 activity.