Another mutation that results in the substitution of an unpaired cysteine residue in the extracellular domain of FGFR3 in thanatophoric dysplasia type I

Geranylgeranyltransferase type-I (GGTase-I) represents an important drug target since it contributes to the function of many proteins that are involved in tumor development and metastasis. This led to the development of GGTase-I inhibitors as anti-cancer drugs blocking the protein function and membrane association of e.g., Rap subfamilies that are involved in cell differentiation and cell growth. In the present study, we developed a new NanoBiT assay to monitor the interaction of human GGTase-I and its substrate Rap1B. Different Rap1B prenylation-deficient mutants (C181G, C181S, and ΔCQLL) were designed and investigated for their interaction with GGTase-I. While the Rap1B mutants C181G and C181S still exhibited interaction with human GGTase-I, mutant ΔCQLL, lacking the entire CAAX motif (defined by a cysteine residue, two aliphatic residues, and the C-terminal residue), showed reduced interaction. Moreover, a specific, peptidomimetic and competitive CAAX inhibitor was able to block the interaction of Rap1B with GGTase-I. Furthermore, activation of both Gαs-coupled human adenosine receptors, A2A (A2AAR) and A2B (A2BAR), increased the interaction between GGTase-I and Rap1B, probably representing a way to modulate prenylation and function of Rap1B. Thus, A2AAR and A2BAR antagonists might be promising candidates for therapeutic intervention for different types of cancer that overexpress Rap1B. Finally, the NanoBiT assay provides a tool to investigate the pharmacology of GGTase-I inhibitors.

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The Carboxy-Terminal Domain of Glycoprotein N of Human Cytomegalovirus Is Required for Virion Morphogenesis

Journal of Virology ◽

10.1128/jvi.01463-06 ◽

2007 ◽

Vol 81 (10) ◽

pp. 5212-5224 ◽

Cited By ~ 32

Author(s):

Michael Mach ◽

Karolina Osinski ◽

Barbara Kropff ◽

Ursula Schloetzer-Schrehardt ◽

Magdalena Krzyzaniak ◽

...

Keyword(s):

Human Cytomegalovirus ◽

Critical Role ◽

Point Mutations ◽

Cysteine Residue ◽

Cysteine Residues ◽

Type I ◽

Terminal Domain ◽

Carboxy Terminal Domain ◽

Carboxy Terminal ◽

Assembly Compartment

ABSTRACT Glycoproteins M and N (gM and gN, respectively) are among the few proteins that are conserved across the herpesvirus family. The function of the complex is largely unknown. Whereas deletion from most alphaherpesviruses has marginal effects on the replication of the respective viruses, both proteins are essential for replication of human cytomegalovirus (HCMV). We have constructed a series of mutants in gN to study the function of this protein. gN of HCMV is a type I glycoprotein containing a short carboxy-terminal domain of 14 amino acids, including two cysteine residues directly adjacent to the predicted transmembrane anchor at positions 125 and 126. Deletion of the entire carboxy-terminal domain as well as substitution with the corresponding region from alpha herpesviruses or mutations of both cysteine residues resulted in a replication-incompetent virus. Recombinant viruses containing point mutations of either cysteine residue could be generated. These viruses were profoundly defective for replication. Complex formation of the mutant gNs with gM and transport of the complex to the viral assembly compartment appeared unaltered compared to the wild type. However, in infected cells, large numbers of capsids accumulated in the cytoplasm that failed to acquire an envelope. Transiently expressed gN was shown to be modified by palmitic acid at both cysteine residues. In summary, our data suggest that the carboxy-terminal domain of gN plays a critical role in secondary envelopment of HCMV and that palmitoylation of gN appears to be essential for function in secondary envelopment of HCMV and virus replication.

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Camera G, Baldi M, Strisciuglio P, Concolino D, Mastroiacovo P, Baffico M. 2001. Occurrence of thanatophoric dysplasia type I (R248C) and hypochondroplasia (N540K) mutations in two patients with achondroplasia phenotype. Am J Med Genet 104:277-281.

American Journal of Medical Genetics ◽

10.1002/ajmg.10470 ◽

2002 ◽

Vol 110 (2) ◽

pp. 193-193 ◽

Cited By ~ 1

Keyword(s):

Type I ◽

Thanatophoric Dysplasia

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A point mutation in the extracellular domain activates LET-23, the Caenorhabditis elegans epidermal growth factor receptor homolog.

Molecular and Cellular Biology ◽

10.1128/mcb.16.2.529 ◽

1996 ◽

Vol 16 (2) ◽

pp. 529-537 ◽

Cited By ~ 48

Author(s):

W S Katz ◽

G M Lesa ◽

D Yannoukakos ◽

T R Clandinin ◽

J Schlessinger ◽

...

Keyword(s):

Epidermal Growth Factor Receptor ◽

Caenorhabditis Elegans ◽

Growth Factor ◽

Epidermal Growth Factor ◽

Point Mutation ◽

Growth Factor Receptor ◽

Extracellular Domain ◽

Cysteine Residue ◽

Loss Of Function ◽

Epidermal Growth

The let-23 gene encodes a Caenorhabditis elegans homolog of the epidermal growth factor receptor (EGFR) necessary for vulval development. We have characterized a mutation of let-23 that activates the receptor and downstream signal transduction, leading to excess vulval differentiation. This mutation alters a conserved cysteine residue in the extracellular domain and is the first such point mutation in the EGFR subfamily of tyrosine kinases. Mutation of a different cysteine in the same subdomain causes a strong loss-of-function phenotype, suggesting that cysteines in this region are important for function and nonequivalent. Vulval precursor cells can generate either of two subsets of vulval cells (distinct fates) in response to sa62 activity. The fates produced depended on the copy number of the mutation, suggesting that quantitative differences in receptor activity influence the decision between these two fates.

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