Autophagy is an intracellular degradation system that delivers cytoplasmic contents to the lysosome for degradation. It is a "self-eating" process and plays a "house-cleaner" role in cells. The complex process consists of several sequential steps-induction, autophagosome formation, fusion of lysosome and autophagosome, degradation, efflux transportation of degradation products, and autophagic lysosome reformation. In this review, the cellular and molecular regulations of late stage of autophagy, including cellular events after fusion step, are summarized.
Animals ; Autophagy ; physiology ; Humans ; Lysosomes ; metabolism ; physiology

Autophagy is a catabolic process including self-degradation of intracellular components via the lysosomal machinery. The biological behavior can be regarded as defense mechanism, maintaining the cell growth, metabolism and homeostasis etc. To date, plenty of autophagy related genes have been identified. In addition, it has been recognized that autophagy plays important roles in the context of virus infection: it can transport viruses from cytoplasm to lysosome to degrade viruses; it can transfer viral nucleic acid to intracellular sensors to activate innate immunity; it can also present viral antigens to MHC class II molecules to activate adaptive immune responses. Autophagy may serve as a double-edged sword to intracellular pathogens. On one side, autophagy may degrade and clear invading microorganisms by xenophagy; on the other side, some microorganisms may develop mechanisms to escape from autophagy for their survival. In this paper, the notion of autophay and the function of autophagy related genes are reviewed. Furthermore, the association of autophagy with a variety of viruses is discussed.
Animals ; Autophagy ; physiology ; Humans ; Virus Diseases ; immunology

Liver is the largest human digestive gland and the most important metabolic organ. When autophagy was proposed during studying liver lysosomes in the 1960s, it was found that nutrient levels and hormones could influence autophagy activity. Recent studies show that autophagy is not only normal physiological processes, but also involved in the regulation of many pathological processes. This article summarizes the role of liver autophagy in the maintenance of homeostasis in the healthy liver, and provides new ideas for liver physiology and treating diseases associated with autophagy disorders.
Animals ; Autophagy ; Homeostasis ; Humans ; Liver ; physiology

Apoptosis ; physiology ; Autophagy ; physiology ; Diabetic Cardiomyopathies ; physiopathology ; Humans

Autophagy, is an essential cellular process involving self-degradation of intracellular components via the lysosome, which plays the Janus role in cancer initiation and progression. Caveolin-1, a marker protein of caveolae, functions as scaffolding protein mediating many physiological and pathological processes including caveolae biogenensis, vesicular transport, cholesterol homeostasis, signal transduction and tumorigenesis. Recently, many reports showed that autophagy of tumor cells associated with stromal Cav-1. We reviewed that the relationship between autophagy and Cav-1 involved in tumorigenesis and development.
Animals ; Autophagy ; physiology ; Caveolin 1 ; physiology ; Humans ; Neoplasms ; pathology ; physiopathology

In recent years, the study of autophagy in spinal cord injury (SCI) gradually becomes the hot spot. However, the function of autophagy in the injured spinal cord is still controversial. In order to further understand the role of autophagy after SCI, we summarized the activation of autophagy, autophagic cell death, the relationship between autophagy and apoptosis, the function of autophagy in promoting the molecular metabolism and the role of autophagy after spinal cord injury. We concluded that the role of autophagy after SCI is a double-edged sword. Upregulating the level of autophagy appropriately can promote damaged proteins metabolism and inhibit apoptosis. However, excessive activation of antophagy may induce autophagic cell dealth. So we consider that the proper regulation of autophagy will be a new target in the treatment of SCI.
Animals ; Apoptosis ; Autophagy ; physiology ; Humans ; Spinal Cord Injuries ; etiology ; pathology

A growing body of evidence has indicated the important role of autophagy receptors in directing ubiquitinated or non-ubiquitinated cargos towards autophagy. Autophagy receptors bind to LC3 (microtubule-associated protein 1 light chain 3) on phagophore and autophagosome membranes, and recognize signals on cargoes in the delivery system of autophagy. However, the diverse domains in the receptor structures determine that their roles would never be limited to autophagy. Up to date, increasing numbers of the receptor proteins have been demonstrated to serve as a molecular link or switch participating in autophagic degradation, apoptosis or cell survival signals. Here, we highlight the non-autophagic roles of these receptor proteins to draw attention to this growing research topic.
Apoptosis ; Autophagy ; Humans ; Microtubule-Associated Proteins ; physiology ; Signal Transduction ; Ubiquitination

Autophagy is a process of bulk degradation of proteins and organelles in cytoplasm.Autophagy has many normal physiological functions in cellular catabolism; therefore is essential for cell homeostasis. In some circumstances autophagy can induces cell death, namely autophagic cell death. Recent studies have suggested that autophagy plays an important role in both normal tissue development and a variety of diseases, including cancer. Therefore, the strategy targeting autophagy pathway may represent a new way of cancer treatment.
Apoptosis ; physiology ; Autophagy ; physiology ; Cell Death ; physiology ; Hematologic Neoplasms ; pathology ; physiopathology ; Signal Transduction

Similar to multicellular animals, single-cell organisms, such as bacteria show the phenomenon of programmed cell death (PCD). The PCD not only can play an important role in various physiological procedures, but also can eliminate bacteria with irreversible injuries. The PCD of single cell in a colony is for the benefits of other bacteria in the same colony to achieve the development and reproduction of the whole colony. Disturbing or destroying such PCD may provide a new way for antibiotic drug research and development.
Autophagy ; physiology ; Bacteria ; cytology ; Staphylococcus aureus ; cytology ; physiology ; Streptococcus pneumoniae ; cytology ; physiology

Autophagy is a specialized cellular pathway involved in maintaining homeostasis by degrading long-lived cellular proteins and organelles. Recent studies have demonstrated that autophagy is utilized by immune systems to protect host cells from invading pathogens and regulate uncontrolled immune responses. During pathogen recognition, induction of autophagy by pattern recognition receptors leads to the promotion or inhibition of consequent signaling pathways. Furthermore, autophagy plays a role in the delivery of pathogen signatures in order to promote the recognition thereof by pattern recognition receptors. In addition to innate recognition, autophagy has been shown to facilitate MHC class II presentation of intracellular antigens to activate CD4 T cells. In this review, we describe the roles of autophagy in innate recognition of pathogens and adaptive immunity, such as antigen presentation, as well as the clinical relevance of autophagy in the treatment of human diseases.
Adaptive Immunity/immunology/*physiology ; Animals ; Antigen Presentation/immunology/physiology ; Autophagy/immunology/*physiology ; Humans ; Major Histocompatibility Complex/immunology/physiology