scholarly journals Limited and Defined Truncation at the C Terminus Enhances Receptor Binding and Degranulation Activity of the Neutrophil-activating Peptide 2 (NAP-2)

1995 ◽  
Vol 270 (11) ◽  
pp. 6338-6344 ◽  
Author(s):  
Jan E. Ehlert ◽  
Frank Petersen ◽  
Michael H. G. Kubbutat ◽  
Johannes Gerdes ◽  
Hans-Dieter Flad ◽  
...  
Keyword(s):  
Receptor Binding ◽  
C Terminus

scholarly journals Structural and functional aspects of the multiplicity of Neu differentiation factors

1994 ◽  
Vol 14 (3) ◽  
pp. 1909-1919
Author(s):  
D Wen ◽  
S V Suggs ◽  
D Karunagaran ◽  
N Liu ◽  
R L Cupples ◽  
...  
Keyword(s):  
Receptor Binding ◽  
Transmembrane Domain ◽  
Structural Heterogeneity ◽  
Binding Activity ◽  
Biologically Active ◽  
Specific Rate ◽  
C Terminus ◽  
Functional Aspects ◽  
Differentiation Factors ◽  
Variable Domains

We used molecular cloning and functional analyses to extend the family of Neu differentiation factors (NDFs) and to explore the biochemical activity of different NDF isoforms. Exhaustive cloning revealed the existence of six distinct fibroblastic pro-NDFs, whose basic transmembrane structure includes an immunoglobulin-like motif and an epidermal growth factor (EGF)-like domain. Structural variation is confined to three domains: the C-terminal portion of the EGF-like domain (isoforms alpha and beta), the adjacent juxtamembrane stretch (isoforms 1 to 4), and the variable-length cytoplasmic domain (isoforms a, b, and c). Only certain combinations of the variable domains exist, and they display partial tissue specificity in their expression: pro-NDF-alpha 2 is the predominant form in mesenchymal cells, whereas pro-NDF-beta 1 is the major neuronal isoform. Only the transmembrane isoforms were glycosylated and secreted as biologically active 44-kDa glycoproteins, implying that the transmembrane domain functions as an internal signal peptide. Extensive glycosylation precedes proteolytic cleavage of pro-NDF but has no effect on receptor binding. By contrast, the EGF-like domain fully retains receptor binding activity when expressed separately, but its beta-type C terminus displays higher affinity than alpha-type NDFs. Likewise, structural heterogeneity of the cytoplasmic tails may determine isoform-specific rate of pro-NDF processing. Taken together, these results suggest that different NDF isoforms are generated by alternative splicing and perform distinct tissue-specific functions.

Structure and Function Relationship of Murine Insulin-like Peptide 5 (INSL5): Free C-Terminus Is Essential for RXFP4 Receptor Binding and Activation

Biochemistry ◽  
2011 ◽  
Vol 50 (39) ◽  
pp. 8352-8361 ◽  
Author(s):  
Alessia Belgi ◽  
Mohammed A. Hossain ◽  
Fazel Shabanpoor ◽  
Linda Chan ◽  
Suode Zhang ◽  
...  
Keyword(s):  
Receptor Binding ◽  
Structure And Function ◽  
C Terminus ◽  
Function Relationship ◽  
Structure And Function Relationship ◽  
And Function ◽  
Relationship Of

scholarly journals Structure and Analysis of R1 and R2 Pyocin Receptor-Binding Fibers

Viruses ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 427 ◽  
Author(s):  
Sergey Buth ◽  
Mikhail Shneider ◽  
Dean Scholl ◽  
Petr Leiman
Keyword(s):  
Cell Surface ◽  
Host Cell ◽  
Receptor Binding ◽  
Binding Sites ◽  
Cell Envelope ◽  
Surface Binding ◽  
Cell Surface Binding ◽  
C Terminus ◽  
Host Cell Surface ◽  
Substrate Binding Sites

The R-type pyocins are high-molecular weight bacteriocins produced by some strains of Pseudomonas aeruginosa to specifically kill other strains of the same species. Structurally, the R-type pyocins are similar to “simple” contractile tails, such as those of phage P2 and Mu. The pyocin recognizes and binds to its target with the help of fibers that emanate from the baseplate structure at one end of the particle. Subsequently, the pyocin contracts its sheath and drives the rigid tube through the host cell envelope. This causes depolarization of the cytoplasmic membrane and cell death. The host cell surface-binding fiber is ~340 Å-long and is attached to the baseplate with its N-terminal domain. Here, we report the crystal structures of C-terminal fragments of the R1 and R2 pyocin fibers that comprise the distal, receptor-binding part of the protein. Both proteins are ~240 Å-long homotrimers in which slender rod-like domains are interspersed with more globular domains—two tandem knob domains in the N-terminal part of the fragment and a lectin-like domain at its C-terminus. The putative substrate binding sites are separated by about 100 Å, suggesting that binding of the fiber to the cell surface causes the fiber to adopt a certain orientation relative to the baseplate and this then triggers sheath contraction.

scholarly journals Identification of residues in the receptor-binding domain (RBD) of the spike protein of human coronavirus NL63 that are critical for the RBD–ACE2 receptor interaction

2008 ◽  
Vol 89 (4) ◽  
pp. 1015-1024 ◽  
Author(s):  
Han-Xin Lin ◽  
Yan Feng ◽  
Gillian Wong ◽  
Liping Wang ◽  
Bei Li ◽  
...  
Keyword(s):  
Receptor Binding ◽  
Binding Domain ◽  
Site Directed Mutagenesis ◽  
Spike Protein ◽  
Receptor Interaction ◽  
Receptor Binding Domain ◽  
Human Coronavirus ◽  
C Terminus ◽  
Group I ◽  
Truncated Variants

Human coronavirus NL63 (NL63), a member of the group I coronaviruses, may cause acute respiratory diseases in young children and immunocompromised adults. Like severe acute respiratory syndrome coronavirus (SARS-CoV), NL63 also employs the human angiotensin-converting enzyme 2 (hACE2) receptor for cellular entry. To identify residues in the spike protein of NL63 that are important for hACE2 binding, this study first generated a series of S1-truncated variants, examined their associations with the hACE2 receptor and subsequently mapped a minimal receptor-binding domain (RBD) that consisted of 141 residues (aa 476–616) towards the C terminus of the S1 domain. The data also demonstrated that the NL63 RBD bound to hACE2 more efficiently than its full-length counterpart and had a binding efficiency comparable to the S1 or RBD of SARS-CoV. A further series of RBD variants was generated using site-directed mutagenesis and random mutant library screening assays, and identified 15 residues (C497, Y498, V499, C500, K501, R518, R530, V531, G534, G537, D538, S540, E582, W585 and T591) that appeared to be critical for the RBD–hACE2 association. These critical residues clustered in three separate regions (designated RI, RII and RIII) inside the RBD, which may represent three receptor-binding sites. These results may help to delineate the molecular interactions between the S protein of NL63 and the hACE2 receptor, and may also enhance our understanding of the pathogenesis of NL63 and SARS-CoV.

scholarly journals Second-Site Changes Affect Viability of Amphotropic/Ecotropic Chimeric Enveloped Murine Leukemia Viruses

2000 ◽  
Vol 74 (2) ◽  
pp. 899-913 ◽  
Author(s):  
Lucille O'Reilly ◽  
Monica J. Roth
Keyword(s):  
Receptor Binding ◽  
Single Point ◽  
Cell Types ◽  
Binding Domain ◽  
Receptor Binding Domain ◽  
Rich Region ◽  
C Terminus ◽  
Nih 3T3 ◽  
Proline Rich Region ◽  
Murine Leukemia

ABSTRACT Chimeras were previously generated between the ecotropic (Moloney-MuLV) and amphotropic (4070A) SU and TM proteins of murine leukemia virus (MuLV). After passage in D17 cells, three chimeras with junctions in the C terminus of SU (AE5, AE6, and AE7), showed improved kinetics of viral spreading, suggesting that they had adapted. Sequencing of the viruses derived from the D17 cell lines revealed second-site changes within the env gene. Changes were detected in the receptor binding domain, the proline-rich region, the C terminus of SU, and the ectodomain of TM. Second-site changes were subcloned into the parental DNA, singly and in combination, and tested for viability. All viruses had maintained their original cloned mutations and junctions. Reconstruction and passage of AE7 or AE6 virus with single point mutations recovered the additional second-site changes identified in the parental population. The AE5 isolate required changes in the VRA, the VRC, the VRB-hinge region, and the C terminus of SU for efficient infection. Passage of virus, including the parental 4070A, in D17 cells resulted in a predominant G100R mutation within the receptor binding domain. Viruses were subjected to titer determination in three cell types, NIH 3T3, canine D17, and 293T. AE6 viruses with changes in the proline-rich region initially adapted for growth on D17 cells could infect all cell types tested. AE6-based chimeras with additional mutations in the C terminus of SU could infect D17 and 293T cells. Infection of NIH 3T3 cells was dependent on the proline-rich mutation. AE7-based chimeras encoding L538Q and G100R were impaired in infecting NIH 3T3 and 293T cells.

scholarly journals Structural and functional aspects of the multiplicity of Neu differentiation factors.

1994 ◽  
Vol 14 (3) ◽  
pp. 1909-1919 ◽  
Author(s):  
D Wen ◽  
S V Suggs ◽  
D Karunagaran ◽  
N Liu ◽  
R L Cupples ◽  
...  
Keyword(s):  
Receptor Binding ◽  
Transmembrane Domain ◽  
Structural Heterogeneity ◽  
Binding Activity ◽  
Biologically Active ◽  
Specific Rate ◽  
C Terminus ◽  
Functional Aspects ◽  
Differentiation Factors ◽  
Variable Domains

We used molecular cloning and functional analyses to extend the family of Neu differentiation factors (NDFs) and to explore the biochemical activity of different NDF isoforms. Exhaustive cloning revealed the existence of six distinct fibroblastic pro-NDFs, whose basic transmembrane structure includes an immunoglobulin-like motif and an epidermal growth factor (EGF)-like domain. Structural variation is confined to three domains: the C-terminal portion of the EGF-like domain (isoforms alpha and beta), the adjacent juxtamembrane stretch (isoforms 1 to 4), and the variable-length cytoplasmic domain (isoforms a, b, and c). Only certain combinations of the variable domains exist, and they display partial tissue specificity in their expression: pro-NDF-alpha 2 is the predominant form in mesenchymal cells, whereas pro-NDF-beta 1 is the major neuronal isoform. Only the transmembrane isoforms were glycosylated and secreted as biologically active 44-kDa glycoproteins, implying that the transmembrane domain functions as an internal signal peptide. Extensive glycosylation precedes proteolytic cleavage of pro-NDF but has no effect on receptor binding. By contrast, the EGF-like domain fully retains receptor binding activity when expressed separately, but its beta-type C terminus displays higher affinity than alpha-type NDFs. Likewise, structural heterogeneity of the cytoplasmic tails may determine isoform-specific rate of pro-NDF processing. Taken together, these results suggest that different NDF isoforms are generated by alternative splicing and perform distinct tissue-specific functions.

scholarly journals Displacement of the C Terminus of Herpes Simplex Virus gD Is Sufficient To Expose the Fusion-Activating Interfaces on gD

2013 ◽  
Vol 87 (23) ◽  
pp. 12656-12666 ◽  
Author(s):  
John R. Gallagher ◽  
Wan Ting Saw ◽  
Doina Atanasiu ◽  
Huan Lou ◽  
Roselyn J. Eisenberg ◽  
...  
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Membrane Fusion ◽  
Receptor Binding ◽  
Viral Entry ◽  
Tertiary Structure ◽  
Host Cells ◽  
Binding Interface ◽  
C Terminus ◽  
Simplex Virus

Viral entry by herpes simplex virus (HSV) is executed and tightly regulated by four glycoproteins. While several viral glycoproteins can mediate viral adhesion to host cells, only binding of gD to cellular receptor can activate core fusion proteins gB and gH/gL to execute membrane fusion and viral entry. Atomic structures of gD bound to receptor indicate that the C terminus of the gD ectodomain must be displaced before receptor can bind to gD, but it is unclear which conformational changes in gD activate membrane fusion. We rationally designed mutations in gD to displace the C terminus and observe if fusion could be activated without receptor binding. Using a cell-based fusion assay, we found that gD V231W induced cell-cell fusion in the absence of receptor. Using recombinant gD V231W protein, we observed binding to conformationally sensitive antibodies or HSV receptor and concluded that there were changes proximal to the receptor binding interface, while the tertiary structure of gD V231W was similar to that of wild-type gD. We used a biosensor to analyze the kinetics of receptor binding and the extent to which the C terminus blocks binding to receptor. We found that the C terminus of gD V231W was enriched in the open or displaced conformation, indicating a mechanism for its function. We conclude that gD V231W triggers fusion through displacement of its C terminus and that this motion is indicative of how gD links receptor binding to exposure of interfaces on gD that activate fusion via gH/gL and gB.

scholarly journals Receptor-Induced Conformational Changes in the SU Subunit of the Avian Sarcoma/Leukosis Virus A Envelope Protein: Implications for Fusion Activation

2005 ◽  
Vol 79 (6) ◽  
pp. 3488-3499 ◽  
Author(s):  
Sue E. Delos ◽  
Jesse A. Godby ◽  
Judith M. White
Keyword(s):  
Receptor Binding ◽  
Conformational Changes ◽  
Fusion Reaction ◽  
Helical Structure ◽  
Low Ph ◽  
Full Length ◽  
Mutant Proteins ◽  
C Terminus ◽  
Subsequent Effect ◽  
Avian Sarcoma

ABSTRACT The avian sarcoma/leukosis virus (ASLV) is activated for fusion by a two-step mechanism. For ASLV subgroup A (ASLV-A), association with its receptor (Tva) at neutral pH converts virions to a form that can bind target membranes and, in some assays, induce the lipid-mixing stage of fusion. Low pH is necessary to complete the fusion reaction. ASLV-A env (EnvA) exists on the viral surface as a trimer of heterodimers consisting of receptor binding (SU-A) and fusion-mediating (TM-A) subunits. As the receptor binding and fusion-mediating functions reside in separate subunits, we hypothesize that SU-A and TM-A are conformationally coupled. To begin to understand the effect of the binding of a soluble 47-residue domain of the receptor (sTva) on this coupling and the subsequent function of low pH, we prepared recombinant proteins representing full-length SU-A and a nested set of deletion mutant proteins. Full-length SU-A binds sTva with high affinity, but even small deletions at either the N or the C terminus severely impair sTva binding. We have purified the full-length SU-A subunit and characterized its interactions with sTva and the subsequent effect of low pH on the complex. sTva binds SU-A with an apparent KD of 3 pM. Complex formation occludes hydrophobic surfaces and tryptophan residues and leads to a partial loss of α-helical structure in SU-A. Low pH does not alter the off rate for the complex, further alter the secondary structure of SU-A, or induce measurable changes in tryptophan environment. The implications of these findings for fusion are discussed.

Sign in / Sign up

Export Citation Format

Share Document