Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0030305 (pancreatitis)
 16,014 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To characterize the emergency program set up by pancreatic cells in response to pancreatitis, we established the phenotype of the pancreatitis-affected pancreas by characterizing a large number of its transcripts. In this report, we describe the cloning, sequencing, and expression pattern of a new gene, named VMP1 (vacuole membrane protein 1). The VMP1 mRNA codes for a putative protein of 406 amino acids. In situ hybridization studies revealed that pancreatic expression of VMP1 mRNAs was restricted to the acinar cells. Interestingly, VMP1 mRNA was also overexpressed in kidney after transient ischemic injury. However, many healthy tissues express VMP1 mRNA. Structure analysis suggested that VMP1 is a transmembrane protein with six hydrophobic regions. VMP1/EGFP fusion protein was located to the Golgi apparatus and the endoplasmic reticulum area. Expression of this protein promoted the formation of intracytoplasmatic vacuoles and VMP1/EGFP was located to the membranes of these vacuoles. Cells overexpressing this protein died after 48 h. In conclusion, we have identified a new stress-induced gene which codes for a transmembrane protein that, when overexpressed, promotes formation of intracellular vacuoles followed by cell death.
 ...
PMID:Cloning and expression of the rat vacuole membrane protein 1 (VMP1), a new gene activated in pancreas with acute pancreatitis, which promotes vacuole formation. 1178 47

Vacuole membrane protein 1 (Vmp1) is membrane protein of unknown molecular function that has been associated with pancreatitis and cancer. The social amoeba Dictyostelium discoideum has a vmp1-related gene that we identified previously in a functional genomic study. Loss-of-function of this gene leads to a severe phenotype that compromises Dictyostelium growth and development. The expression of mammalian Vmp1 in a vmp1(-) Dictyostelium mutant complemented the phenotype, suggesting a functional conservation of the protein among evolutionarily distant species and highlights Dictyostelium as a valid experimental system to address the function of this gene. Dictyostelium Vmp1 is an endoplasmic reticulum protein necessary for the integrity of this organelle. Cells deficient in Vmp1 display pleiotropic defects in the secretory pathway and organelle biogenesis. The contractile vacuole, which is necessary to survive under hypoosmotic conditions, is not functional in the mutant. The structure of the Golgi apparatus, the function of the endocytic pathway and conventional protein secretion are also affected in these cells. Transmission electron microscopy of vmp1(-) cells showed the accumulation of autophagic features that suggests a role of Vmp1 in macroautophagy. In addition to these defects observed at the vegetative stage, the onset of multicellular development and early developmental gene expression are also compromised.
 ...
PMID:Vacuole membrane protein 1 is an endoplasmic reticulum protein required for organelle biogenesis, protein secretion, and development. 1855 Jul 98

Autophagy has recently elicited significant attention as a mechanism that either protects or promotes cell death, although different autophagy pathways, and the cellular context in which they occur, remain to be elucidated. We report a thorough cellular and biochemical characterization of a novel selective autophagy that works as a protective cell response. This new selective autophagy is activated in pancreatic acinar cells during pancreatitis-induced vesicular transport alteration to sequester and degrade potentially deleterious activated zymogen granules. We have coined the term "zymophagy" to refer to this process. The autophagy-related protein VMP1, the ubiquitin-protease USP9x, and the ubiquitin-binding protein p62 mediate zymophagy. Moreover, VMP1 interacts with USP9x, indicating that there is a close cooperation between the autophagy pathway and the ubiquitin recognition machinery required for selective autophagosome formation. Zymophagy is activated by experimental pancreatitis in genetically engineered mice and cultured pancreatic acinar cells and by acute pancreatitis in humans. Furthermore, zymophagy has pathophysiological relevance by controlling pancreatitis-induced intracellular zymogen activation and helping to prevent cell death. Together, these data reveal a novel selective form of autophagy mediated by the VMP1-USP9x-p62 pathway, as a cellular protective response.
 ...
PMID:Zymophagy, a novel selective autophagy pathway mediated by VMP1-USP9x-p62, prevents pancreatic cell death. 2117 55

The Vacuole Membrane Protein 1 -VMP1- is a pancreatitis-associated transmembrane protein whose expression triggers autophagy in several human diseases. In the current study, we unveil the mechanism through which this protein induces autophagosome formation in mammalian cells. We show that VMP1 autophagy-related function requires its 20-aminoacid C-terminus hydrophilic domain (VMP1-AtgD). This is achieved through its direct binding to the BH3 motif of Beclin 1 leading to the formation of a complex with the Class III phosphatidylinositol-3 kinase (PI3K) hVps34, a key positive regulator of autophagy, at the site where autophagosomes are generated. This interaction also concomitantly promotes the dissociation of Bcl-2, an autophagy inhibitor, from Beclin 1. Moreover, we show that the VMP1-Beclin 1-hVps34 complex favors the association of Atg16L1 and LC3 with the autophagosomal membranes. Collectively, these findings reveal that VMP1 expression recruits and activates the Class III PI3K complex at the site of autophagosome formation during mammalian autophagy.
 ...
PMID:The VMP1-Beclin 1 interaction regulates autophagy induction. 2331 80

Pancreatitis is an inflammatory disease that both facilitates and accelerates the transformation of pancreatic cells upon activation of the KRAS oncogene. Autophagy is proposed to be one of the cellular mechanisms contributing to pancreatic carcinogenesis, especially during initial stages in which the KRAS oncogene appears to play a key role. Autophagy is also strongly induced during pancreatitis by the overexpression of VMP1. We recently developed a genetically engineered mouse model in which the VMP1 protein is induced simultaneously with the activation of the oncogene KrasG12D specifically in the pancreas, by the addition of doxycycline to a water drink. Using this sophisticated animal model, we can affirm that pancreatic autophagy, induced during pancreatitis by the overexpression of VMP1, promotes the development of precancerous lesions when induced by the mutated KRAS. In addition, the treatment of these mice with chloroquine, an inhibitor of autophagic flux, reverses the effects of VMP1 in pancreatic cancer induced by the KRAS oncogene. Overall, these results bear both mechanistic and biomedical relevance for further understanding and potentially targeting pathways that are critical for initiating pancreatic carcinogenesis, particularly if associated with pancreatitis.
 ...
PMID:Autophagy Induced during Pancreatitis Promotes KRAS-Dependent Transformation in the Pancreas. 2783

The pancreatic adenocarcinoma initiation results from the interaction of genetic events combined with multiple other factors. Among the genetic alterations that contribute to the pathogenesis of this disease, the mutation of the KRAS oncogene is required but not sufficient to trigger this cancer. Pancreatitis, an inflammatory disease, facilitates and accelerates the transformation of pancreatic cells when the KRAS oncogene is mutated. Of note, the repertoire of molecular mediators of pancreatitis which are responsible of the promotion of KRAS-mediated transformation is not completely defined. Importantly, autophagy has been proposed as one of the cellular mechanisms contributing to pancreatic carcinogenesis, especially in the initial phases, in which the oncogene KRAS appears to play its leading role. In addition, autophagy is strongly induced during pancreatitis. Although some aspects of autophagy in pancreatic cancer development are not completely established, we can affirm that overexpression of VMP1, an inducer of autophagy which is specifically activated in pancreas during pancreatitis, improves the development of pancreatic precancerous lesions PanINs when the oncogene KRAS is mutated. In addition, inhibition of the autophagic flux with chloroquine inhibits the KRAS pro-tumor effect in the pancreas. In conclusion, activation of expression of VMP1 improves the pro-tumor role of KRAS in pancreas.
 ...
PMID:[Autophagy contributes to the initiation of pancreatic cancer]. 2836 22