A processed form of the Spatzle protein defines dorsal-ventral polarity in the Drosophila embryo

Development ◽  
1994 ◽  
Vol 120 (5) ◽  
pp. 1243-1250 ◽  
Author(s):  
D.S. Schneider ◽  
Y. Jin ◽  
D. Morisato ◽  
K.V. Anderson
Keyword(s):  
Extracellular Space ◽  
Active Form ◽  
Ventral Side ◽  
Proteolytic Processing ◽  
Drosophila Embryo ◽  
Translation Product ◽  
Primary Translation Product ◽  
Early Drosophila Embryo ◽  
Extracellular Factor ◽  
Processed Form

Stein et al. (1991) identified a soluble, extracellular factor that induces ventral structures at the site where it is injected in the extracellular space of the early Drosophila embryo. This factor, called polarizing activity, has the properties predicted for a ligand for the transmembrane receptor encoded by the Toll gene. Using a bioassay to follow activity, we purified a 24 × 10(3) M(r) protein that has polarizing activity. The purified protein is recognized by antibodies to the C-terminal half of the Spatzle protein, indicating that this polarizing activity is a product of the spatzle gene. The purified protein is smaller than the primary translation product of spatzle, suggesting that proteolytic processing of Spatzle on the ventral side of the embryo is required to generate the localized, active form of the protein.

scholarly journals Proteolytic Processing of a Serotype 8 Human Astrovirus ORF2 Polyprotein

2002 ◽  
Vol 76 (16) ◽  
pp. 7996-8002 ◽  
Author(s):  
Ernesto Méndez ◽  
Teresa Fernández-Luna ◽  
Susana López ◽  
Martha Méndez-Toss ◽  
Carlos F. Arias
Keyword(s):  
Host Cell ◽  
Immunoblot Analysis ◽  
Proteolytic Processing ◽  
Amino Terminus ◽  
Translation Product ◽  
Carboxy Terminus ◽  
Trypsin Treatment ◽  
Primary Translation Product ◽  
Viral Particles ◽  
Human Astrovirus

ABSTRACT Astroviruses require the proteolytic cleavage of the capsid protein to infect the host cell. Here we describe the processing pathway of the primary translation product of the structural polyprotein (ORF2) encoded by a human astrovirus serotype 8 (strain Yuc8). The primary translation product of ORF2 is of approximately 90 kDa, which is subsequently cleaved to yield a 70-kDa protein (VP70) which is assembled into the viral particles. Limited trypsin treatment of purified particles containing VP70 results in the generation of polypeptides VP41 and VP28, which are then further processed to proteins of 38.5, 35, and 34 kDa and 27, 26, and 25 kDa, respectively. VP34, VP27 and VP25 are the predominant proteins in fully cleaved virions, which correlate with the highest level of infectivity. Processing of the VP41 protein to yield VP38.5 to VP34 polypeptides occurred at its carboxy terminus, as suggested by immunoblot analysis using hyperimmune sera to different regions of the ORF2, while processing of VP28 to generate VP27 and VP25 occurred at its carboxy and amino terminus, respectively, as determined by immunoblot, as well as by N-terminal sequencing of those products. Based on these data, the processing pathway for the 90-kDa primary product of astrovirus Yuc8 ORF2 is presented.

In vitro studies on the subcellular location of glucosidase I and glucosidase II in dog pancreas

1986 ◽  
Vol 6 (9) ◽  
pp. 827-834 ◽  
Author(s):  
Ernst Bause ◽  
Roland Günther ◽  
Jürgen Schweden ◽  
Ulrich Tillmann
Keyword(s):  
Molecular Mass ◽  
Consensus Sequence ◽  
Proteolytic Processing ◽  
Translation System ◽  
Translation Product ◽  
Glycosidase Inhibitors ◽  
Glucosidase Ii ◽  
Primary Translation Product ◽  
Dog Pancreas

When programmed with yeast prepro-α-factor mRNA, the heterologous reticulocyte/dog pancreas translation system synthesizes two pheromone related polypeptides, a cytosolically located primary translation product (pp-α-Fcyt, 21 kDa) and a membrane-specific and multiply glycosylated e-factor precursor (pp-α-F3, 27.5 kDa). Glycosylation of the membrane specific pp-α-F3 species is competitively inhibited by synthetic peptides containing the consensus sequence Asn-Xaa-Thr as indicated by a shift of its molecular mass from 27.5 kDa to about 19.5 kDa (pp-α-F0), whereas the primary translation product pp-α-F cyt is not affected. Likewise, only the glycosylated pp-α-F3 structure is digested by Endo H yielding a polypeptide with a molecular mass between PP-α-F0 and pp-α-F cyt. These observations strongly suggest that the primary translation product is proteolytically processed during/on its translocation into the lumen of the microsomal vesicles. We believe that this proteolytic processing is due to the cleavage of a signal sequence from the pp-α-F cyt species, although this interpretation contradicts previous data from other groups. The distinct effect exerted by various glycosidase inhibitors (e.g. 1-deoxynojirimycin, N-methyl-dNM, 1-deoxymannojirimycin) on the electrophoretic mobility of the pp-α-F3 polypeptide indicates that its oligosaccharide chains are processed to presumbly Man9-GlcNAc2 structures under the in vitro conditions of translation. This oligosaccharide processing is most likely to involve the action of glucosidase I and glucosidase II as follows from the specificity of the glycosidase inhibitors applied and the differences of the molecular mass observed in their presence. In addition, several arguments suggest that both trimming enzymes are located in the lumen of the microsomal vesicles derived from endoplasmic reticulum membranes.

scholarly journals Divergence of Stp1 and Stp2 Transcription Factors in Candida albicans Places Virulence Factors Required for Proper Nutrient Acquisition under Amino Acid Control

2005 ◽  
Vol 25 (21) ◽  
pp. 9435-9446 ◽  
Author(s):  
Paula Martínez ◽  
Per O. Ljungdahl
Keyword(s):  
Amino Acids ◽  
Candida Albicans ◽  
Transcription Factors ◽  
Amino Acid ◽  
Active Form ◽  
Amino Acid Uptake ◽  
Extracellular Proteins ◽  
Proteolytic Processing ◽  
Acid Uptake ◽  
Processed Form

ABSTRACT Candida albicans possesses a plasma membrane-localized sensor of extracellular amino acids. Here, we show that in response to amino acids, this sensor induces the proteolytic processing of two latent transcription factors, Stp1 and Stp2. Processing removes negative regulatory motifs present in the N-terminal domains of these factors. Strikingly, Stp1 and Stp2 exhibit a clear dichotomy in the genes they transactivate. The shorter active form of Stp2 activates genes required for amino acid uptake. The processed form of Stp1 activates genes required for degradation of extracellular protein and uptake of peptides, and cells lacking Stp1 do not express the secreted aspartyl protease SAP2 or the oligopeptide transporter OPT1. Consequently, stp1 null mutants are unable to grow on media with protein as the sole nitrogen source. Cells expressing the STP1* allele that encodes a protein lacking the inhibitory N-terminal domain constitutively express SAP2 and OPT1 even in the absence of extracellular proteins or peptides. Also, we show that Stp1 levels, but not Stp2 levels, are downregulated in the presence of millimolar concentrations of extracellular amino acids. These results define the hierarchy of regulatory mechanisms that differentially control two discrete pathways for the assimilation of nitrogen.

The Cytoskeleton of the Early Drosophila Embryo

1986 ◽  
Vol 1986 (Supplement 5) ◽  
pp. 311-328 ◽  
Author(s):  
R. M. WARN
Keyword(s):  
Drosophila Embryo ◽  
Early Drosophila Embryo

scholarly journals Assembly of yolk spindles in the early Drosophila embryo

2003 ◽  
Vol 120 (4) ◽  
pp. 441-454 ◽  
Author(s):  
Maria Giovanna Riparbelli ◽  
Giuliano Callaini
Keyword(s):  
Drosophila Embryo ◽  
Early Drosophila Embryo
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