The basket-associated Mlp1 and Mlp2 (Tpr in vertebrates) and Pml39 proteins are involved in sorting proper and improper mRNPs for translocation and retention, respectively (reviewed in Fasken and Corbett 2009).
This retention could result from improper presentation of the di-acidic motif and/or from misfolding of the mutant protein.
Therefore, it could be speculated that these highly conserved substrate-unspecific parts of the protein may have important structural functions and polymorphism affecting them lead to improper structure of the protein and its retention in the endoplasmic reticulum.
We interpret this result as epitope insertion in this portion of the protein causing improper maturation and processing of the protein (retention in the endoplasmic reticulum), preventing functional insertion in the membrane as determined by the absence of an immunofluorescence signal in transfected cells (data not shown) and ultimately leading to absence of detectable transport.
They deal, respectively, with the unauthorized removal and retention of classified material, and the improper gathering, transmission or loss of information relating to the national defense.
Those calling for Clinton to be prosecuted tend to focus on two provisions of federal law--sections 1924 and 793 of Title 18 of the United States Code--dealing, respectively, with the unauthorized removal and retention of classified material, and the improper gathering, transmission or loss of information relating to the national defense.
Its retention in all parts of the bridge, or improper outflow, is causing corrosion of the steel and the concrete.
In conventional eukaryotic expression systems ER retention of recombinant GPCRs and transporters can indicate improper folding and is often a problem e.g. for expression in yeast.
While the exact function of CMG2 remains to be unravelled, our studies show that the majority of the HFS mutations lead to loss of function due either to the instability of the CMG2 messenger in the case of frame-shift mutations in exon 13 or to improper folding of the ectodomain of the protein in the ER followed by ER retention and degradation.
Misfolding can result in degradation or retention in the ER and Golgi, respectively [ 122], and the formation of improper disulfide bonds are one possible reason for the small percentage of active enzyme produced, for example in relation to the secreted fraction in the case of T. reesei CBH1 expressed in P. pastoris [ 123].
