among the food products, grains play an important role in the consumption patterns of people, especially in the developing countries. since iran's main source of public dietary energy comes directly from grains, investigating and identifying the determinants of import of these products can be an important step towards food security. most experimental studies consider import of grains as only a ...

Import of tRNA into the mitochondrial matrix of Trypanosoma brucei was reconstituted in vitro. Efficient import required the hydrolysis of externally added ATP and was shown to be a carrier-mediated process depending on proteinaceous receptors on the surface of mitochondria. A partly synthetic tRNA(Tyr) as well as a physiological tRNA(Lys) were imported along the same pathway. Contrary to impor...

Using a granular model of international trade, we study the rationale and implications various government interventions targeted at large individual firms. In antitrust regulation, governments face an incentive to be overly lenient towards domestic mergers in comparative advantage sectors. trade policy, targeting foreign exporters rather than entire sectors minimizes pass-through import tariffs...

Mitochondrial biogenesis is accompanied by an increased expression of components of the protein import machinery, as well as increased import of proteins destined for the matrix. We evaluated the role of the outer membrane receptor Tom20 by varying its expression and measuring changes in the import of malate dehydrogenase (MDH) in differentiating C2C12 muscle cells. Cells transfected with Tom20...

The import of proteins into peroxisomes possesses many unusual features such as the ability to import folded proteins, and a surprising diversity of targeting signals with differing affinities that can be recognized by the same receptor. As understanding of the structure and function of many components of the protein import machinery has grown, an increasingly complex network of factors affecti...

Leucoplasts are important organelles for the synthesis and storage of starch, lipids and proteins. However, molecular mechanism of protein import into leucoplasts and how it differs from that of import into chloroplasts remain unknown. We used pea seedlings for both chloroplast and leucoplast isolations to compare within the same species. We further optimized the isolation and import conditions...

The nuclear protein regulator of chromosome condensation 1 (RCC1) stimulates guanine nucleotide exchange on a protein, Ran, that is required for nuclear protein import. In the present report, we confirm that RCC1 is also required for nuclear protein import in tsBN2 hamster cells in vivo. The thermolability of nuclear protein import in tsBN2 cells was suppressed by microinjection of purified Ran...

Mitochondrial protein import is thought to involve the sequential interaction of preproteins with binding sites on cis and trans sides of the membranes. For translocation across the outer membrane, preproteins first interact with the cytosolic domains of import receptors (cis) and then are translocated through a general import pore, in a process proposed to involve binding to a trans site on th...

The NH2 terminus of the yeast F1-ATPase beta subunit precursor directs the import of this protein into mitochondria. To define the functionally important components of this import signal, oligonucleotide-directed mutagenesis was used to introduce a series of deletion and missense mutations into the gene encoding the F1-beta subunit precursor. Among these mutations were three nonoverlapping dele...