细胞功能测定

Tuberculosis is currently the most devastating human bacterial disease, causing millions of deaths annually and infecting an overwhelming percentage of the global population. Its success as a scourge lies in the ability of Mycobacterium tuberculosis to prevent normal phagolyso ...

Phagocytosis is a process by which invading organisms are taken up by macrophages and targeted to the lysosomes, where they are degraded. However, many pathogens modulate this central process of macrophage-mediated killing by inhibiting their transport to the lysosomes through a vari ...

Interferon-gamma IFN-γ)–induced remodeling of the bacterial phagosome for pathogen clearance elicits the aid of a new family of GTPases termed the p47 IRGs. Members of this group reside primarily on ER-Golgi membranes before translocating to the nascent phagosome within minutes of bac ...

Coxiella burnetii is a bacterial obligate intracellular pathogen that replicates within a spacious parasitophorous vacuole (PV) with lysosomal characteristics. The pathogen actively participates in the biogenesis of its PV by synthesizing proteins that mediate vesicular ...

A unique feature of the intracellular life cycle of Legionella pneumophila is the interaction between the vacuole in which L. pneumophila resides and the endoplasmic reticulum of the host cell. This interaction is crucial for L. pneumophila to establish a niche in which the bacteria can repli ...

Phagocytic antigen-presenting cells (APCs) are involved in innate and adaptive immune responses to bacteria. Adaptive responses to bacteria involve processing of bacterial antigens for presentation by class II major histocompatibility complex (MHC II) molecules and class I MHC ...

The amoeba Dictyostelium discoideum is an established model to study phagocytosis. The sequence of events leading to the internalization and degradation of a particle is conserved in D. discoideum compared to metazoan cells. As its small haploid genome has been sequenced, it is now amenable ...

The ultimate goal of phagosomal maturation is the delivery of internalized, particulate cargo to acidic, hydrolytically competent compartments capable of mediating its degradation. Here we outline in detail three fluorometric techniques that allow the study of phagosomal mat ...

Autophagy and phagocytosis are evolutionarily ancient processes functioning in capture and digestion of material found in the cellular interior and exterior, respectively. In their most primordial form, both processes are involved in cellular metabolism and feeding, supplyi ...

Phagolysosome biogenesis plays a pivotal role in elimination of foreign particles and pathogens by leukocytes. This process is achieved by multiple cycles of membrane fusion between the phagosome and the endosomal system. In vitro reconstitution of phagosome fusion with endosomes ...

Phosphoinositide signaling is essential for successful phagocytosis. Phosphoinositides regulate processes such as actin assembly and the recruitment of molecular motors required for ingestion, as well as fusion events required for the maturation of the phagosome. Phospho ...

Microtubule-associated protein 1A/1B-light chain 3 (LC3) is a soluble protein with a molecular mass of ∼17 kDa that is distributed ubiquitously in mammalian tissues and cultured cells. During autophagy, autophagosomes engulf cytoplasmic components, including cytosolic prot ...

Most proteins need to interact physically with other proteins to be able to perform their biological functions; the identification of new protein-binding partners for a protein of interest may therefore be a key strategy in defining the mechanism of action for a particular protein. Many dif ...

Surveillance mechanisms monitoring genomic integrity operate through signal transduction pathways called checkpoints. Checkpoints are essential to delay cell cycle progression in response to deoxyribonucleic acid (DNA) damage (1,2). These pathways require the coordi ...

The human Rad9-Hus1-Rad1 (9-1-1) and Rad17-RFC40-RFC38-RFC37-RFC36 (hRad17-RFC) protein complexes are important components of the mammalian deoxyribonucleic acid (DNA) damage response. Accumulating evidence from biochemical and molecular modeling studies indicate ...

Many cell cycle transitions are controlled by ubiquitin-mediated proteolysis of key cell cycle regulators (1). The ubiquitin system targets substrates to the proteasome by attaching a polyubiquitin chain (2). The traditional ubiquitin transfer reaction involves a minimum of thr ...

How can bioinformatics tools help to identify particular types of proteins? In general, the answer depends on the type of protein. Alignment methods can identify similarities between two proteins. However, although database search tools are optimized to finding the best possible supe ...

Unlike many of the other topics covered in this book, the difficulty in identifying conserved checkpoint genes lies more in choosing an appropriate method than in carrying out the work. Thus, this chapter concentrates more on the alternative strategies and under which circumstances the ch ...

Chromatin structure, which plays a key role in the regulation of gene expression, is dynamically regulated by diverse posttranslational modifications. Histone-modifying proteins alter chromatin proteins through phosphorylation, adenosine 5′-diphosphate (ADP)-rib ...

Due to the very low titers of human mesenchymal stem cells (MSC) in their niches, namely the bone marrow, an effective approach to isolate and expand those cells ex vivo is required to meet the needs of the increasing MSC clinical applications (e.g., therapy-resistant severe acute graft-versus-h ...