Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001511 (Adhesion)
 5,955 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The fungal pathogen Cryptococcus neoformans has a predilection for the central nervous system (CNS), resulting in devastating meningoencephalitis. At present, it is unclear how C. neoformans traverses the blood-brain barrier (BBB) and causes CNS infection. The present study has examined and characterized the interaction of C. neoformans with human brain microvascular endothelial cells (HBMEC), which constitute the BBB. Adhesion of and transcytosis of HBMEC by C. neoformans was inoculum- and time-dependent and occurred with both encapsulated and acapsulated strains. C. neoformans induced marked morphological changes in HBMEC, for example membrane ruffling, irregular nuclear morphology and swelling of the mitochondria and the ER. These findings suggest that C. neoformans induced actin cytoskeletal reorganization of the host cells. In addition, it was observed that the dephosphorylated form of cofilin was increased during cryptococcal adherence to HBMEC, concomitant with the actin rearrangement. Cryptococcal binding to HBMEC was increased in the presence of Y27632, a Rho kinase (ROCK)-specific inhibitor. Since ROCK activates LIM kinase (LIMK), which phosphorylates cofilin (inactive form), this suggests the involvement of the ROCK-->LIMK-->cofilin pathway. In contrast, the phosphatase inhibitor sodium orthovanadate decreased adherence of Cryptococcus to HBMEC, concomitant with the increase of phosphorylation of cofilin. Furthermore, the tight junction marker protein occludin became Triton-extractable, indicating alteration of tight junctions in brain endothelial cells. This is the first demonstration that C. neoformans is able to adhere to and transcytose across the HBMEC monolayer and alter the cytoskeleton morphology in HBMEC. Further characterization of the interactions between C. neoformans and HBMEC should help the development of novel strategies to prevent cryptococcal meningitis and its associated morbidity.
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PMID:Cryptococcus neoformans induces alterations in the cytoskeleton of human brain microvascular endothelial cells. 1453 40

In cell proliferation, stem cell differentiation, chemoresistance, and tissue organization, the ubiquitous role of YAP/TAZ continues to impact our fundamental understanding in numerous physiological and disease systems. YAP/TAZ is an important signaling nexus integrating diverse mechanical and biochemical signals, such as ECM stiffness, adhesion ligand density, or cell-cell contacts, and thus strongly influences cell fate. Recent studies show that YAP/TAZ mechanical sensing is dependent on RhoA-regulated stress fibers. However, current understanding of YAP/TAZ remains limited due to the unknown interaction between the canonical Hippo pathway and cell tension. Furthermore, the multiscale relationship connecting adhesion signaling to YAP/TAZ activity through cytoskeleton dynamics remains poorly understood. To identify the roles of key signaling molecules in mechanical signal sensing and transduction, we present a, to our knowledge, novel computational model of the YAP/TAZ signaling pathway. This model converts extracellular-matrix mechanical properties to biochemical signals via adhesion, and integrates intracellular signaling cascades associated with cytoskeleton dynamics. We perform perturbations of molecular levels and sensitivity analyses to predict how various signaling molecules affect YAP/TAZ activity. Adhesion molecules, such as FAK, are predicted to rescue YAP/TAZ activity in soft environments via the RhoA pathway. We also found that changes of molecule concentrations result in different patterns of YAP/TAZ stiffness response. We also investigate the sensitivity of YAP/TAZ activity to ECM stiffness, and compare with that of SRF/MAL, which is another important regulator of differentiation. In addition, the model shows that the unresolved synergistic effect of YAP/TAZ activity between the mechanosensing and the Hippo pathways can be explained by the interaction of LIM-kinase and LATS. Overall, our model provides a, to our knowledge, novel platform for studying YAP/TAZ activity in the context of integrating different signaling pathways. This platform can be used to gain, to our knowledge, new fundamental insights into roles of key molecular and mechanical regulators on development, tissue engineering, or tumor progression.
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PMID:A Computational Model of YAP/TAZ Mechanosensing. 2727 71