Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
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Query: EC:3.2.1.26 (
invertase
)
4,927
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Expression of heterologous multispanning membrane proteins in Saccharomyces cerevisiae is a difficult task. Quite often, the use of multicopy plasmids where the foreign gene is under the control of a strong promoter does not guarantee efficient production of the corresponding protein. In the present study, we show that the expression level and/or subcellular localization in S. cerevisiae of a heterologous type of multispanning membrane protein, the proton-translocating inorganic pyrophosphatase (H+-
PPase
), can be changed by fusing it with various suitable N-terminal signal sequences. Chimaeric proteins were constructed by adding the putative N-terminal extra domain of Trypanosoma cruzi H+-
PPase
or the bona fide signal sequence of S. cerevisiae
invertase
Suc2p to H+-
PPase
polypeptides of different organisms (from bacteria to plants) and expressed in a yeast conditional mutant deficient in its cytosolic PPi hydrolysis activity when grown on glucose. Chimaeric constructs not only substantially enhanced H+-
PPase
expression levels in transformed mutant cells, but also allowed functional complementation in those cases in which native H+-
PPase
failed to accomplish it. Activity assays and Western blot analyses demonstrated further the occurrence of most H+-
PPase
in internal membrane fractions of these cells. The addition of N-terminal signal sequences to the vacuolar H+-
PPase
AVP1 from the plant Arabidopsis thaliana, a protein efficiently expressed in yeast in its natural form, alters the subcellular distribution of the chimaeras, suggesting further progression along the secretory sorting pathways, as shown by density gradient ultracentrifugation and in vivo fluorescence microscopy of the corresponding GFP (green fluorescent protein)-H+-
PPase
fusion proteins.
...
PMID:N-terminal chimaeras with signal sequences enhance the functional expression and alter the subcellular localization of heterologous membrane-bound inorganic pyrophosphatases in yeast. 2002 9
Cottonseed, oil, and protein, as the by-products of cotton production, have the potential to provide commodities to meet the increasing demand of renewable bio-fuels and ruminant feed. An increase in crop yield per unit area requires high-yielding cultivar management with an economic nitrogen (N) rate, an optimal N application schedule, high-yielding plant populations and strong seedlings. Whether the integration of these agronomic practices into a coherent management system can increase the productivity of cotton fiber, embryo oil and protein requires experimental elucidation. In this 2-year study, conventional management practices (CM) were used as a control, and two integrated management strategies (IMS
1
and IMS
2
) were considered at two soil fertility levels (high soil fertility and low soil fertility) to analyze the metabolic and biochemical traits of cotton embryos. The results illustrate that the cottonseed, oil, and protein yields for IMS
1
and IMS
2
were significantly higher than those under CM at both soil fertility levels and the fiber yield increased as well. The IMS regulated the maternal photo thermal environment by delaying the flowering date, resulting in increases in the seed weight. In developing cotton embryos, the IMS increased the embryo weight accumulation rate and biomass partitioning into oil and protein, which were associated with high activities of H
+
-ATPase, H
+
-
PPase
, sucrose synthase (SuSy), and cell wall
invertase
(C-INV) and low activities of sucrose phosphate synthase (SPS) and vacuole
invertase
(V-INV). Increased hexoses (D-fructose, D-glucose) content contributed to the oil and protein contents. These results suggest that increased sucrose/H
+
symport, sucrose hydrolysis, hexoses synthesis, and cumulative photo-thermal product (PTP), especially in the early stage of embryo growth, play a dominant role in the high productivity of cotton oil and protein.
...
PMID:Integrated Management Strategies Increase Cottonseed, Oil and Protein Production: The Key Role of Carbohydrate Metabolism. 2819 56
