Article Abstract:
The endoplasmic reticulum (ER) performs several functions. It is the port of entry of membrane and secretory proteins into the central vacuolar system. It also serves as the site of maturation of nascent secretory and membrane proteins to their respective tertiary and quaternary structures. The ER is equipped with a 'quality control' mechanism through which proteins that fail to fold or oligomerize correctly are not allowed to be secreted and are degraded. Such process appears to occur within the organelle.
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
The cystic fibrosis transmembrane conductance regulator (CFTR) is an ATP-binding channel (ABC) transporter and a plasma membrane chloride channel. CFTR is of the traffic ATPase superfamily and chlorine ion channel that seems to need ATP hydrolysis for gating. Investigation of single CFTR chlorine ion channels showed the existence of two open conductance states that are related to each other and to the closed state by an asymmetric cycle of gating events.
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
Rapid cystic fibrosis transmembrane conductance regulator (CFTR) degradation occurs due to ubiquitination. Two strong proteasome inhibitors induce aggregation of polyubiquitinated forms of immature CFTR and inhibit degradation of wild-type and mutant CFTR. Coexpression of a dominant negative ubiquitin mutant also inhibits degradation of CFTR. Degradation is also suppressed in cells having a temperature-sensitive mutation in ubiquitin-activating enzyme.
User Contributions:
Comment about this article or add new information about this topic: