Conservation of a cytoplasmic carboxy-terminal domain of connexin 43, a gap junctional protein, in mammal heart and brain

The m.3243A>G mutation within the mitochondrial mt-tRNALeu(UUR) gene is the most prevalent variant linked to mitochondrial encephalopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome. This pathogenic mutation causes severe impairment of mitochondrial protein synthesis due to alterations of the mutated tRNA, such as reduced aminoacylation and a lack of post-transcriptional modification. In transmitochondrial cybrids, overexpression of human mitochondrial leucyl-tRNA synthetase (LARS2) has proven effective in rescuing the phenotype associated with m.3243A>G substitution. The rescuing activity resides in the carboxy-terminal domain (Cterm) of the enzyme; however, the precise molecular mechanisms underlying this process have not been fully elucidated. To deepen our knowledge on the rescuing mechanisms, we demonstrated the interactions of the Cterm with mutated mt-tRNALeu(UUR) and its precursor in MELAS cybrids. Further, the effect of Cterm expression on mitochondrial functions was evaluated. We found that Cterm ameliorates de novo mitochondrial protein synthesis, whilst it has no effect on mt-tRNALeu(UUR) steady-state levels and aminoacylation. Despite the complete recovery of cell viability and the increase in mitochondrial translation, Cterm-overexpressing cybrids were not able to recover bioenergetic competence. These data suggest that, in our MELAS cell model, the beneficial effect of Cterm may be mediated by factors that are independent of the mitochondrial bioenergetics.

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What’s all the phos about? Insights into the phosphorylation state of the RNA polymerase II C-terminal domain via mass spectrometry

RSC Chemical Biology ◽

10.1039/d1cb00083g ◽

2021 ◽

Author(s):

Blase Matthew LeBlanc ◽

Rosamaria Yvette Moreno ◽

Edwin Escobar ◽

Mukesh Kumar Venkat Ramani ◽

Jennifer S Brodbelt ◽

...

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Phosphorylation State ◽

Terminal Domain ◽

Carboxy Terminal Domain ◽

Protein Encoding ◽

Small Nuclear Rnas ◽

Rnap Ii ◽

Carboxy Terminal ◽

Encoding Genes

RNA polymerase II (RNAP II) is one of the primary enzymes responsible for expressing protein-encoding genes and some small nuclear RNAs. The enigmatic carboxy-terminal domain (CTD) of RNAP II and...

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The signal transducer gp130: Solution structure of the carboxy-terminal domain of the cytokine receptor homology region

Protein Science ◽

10.1110/ps.8.1.5 ◽

2008 ◽

Vol 8 (1) ◽

pp. 5-12 ◽

Cited By ~ 17

Author(s):

Thomas Kernebeck ◽

Stefan Pflanz ◽

Peter C. Heinrich ◽

Axel Wollmer ◽

Joachim Grötzinger ◽

...

Keyword(s):

Solution Structure ◽

Cytokine Receptor ◽

Signal Transducer ◽

Homology Region ◽

Terminal Domain ◽

Carboxy Terminal Domain ◽

Carboxy Terminal

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Study on the association between CTD peptides and zinc(ii)-dipicolylamine appended beta-cyclodextrin

RSC Advances ◽

10.1039/c5ra12374g ◽

2015 ◽

Vol 5 (98) ◽

pp. 80434-80440 ◽

Cited By ~ 1

Author(s):

Saihui Zhang ◽

Yantao Shi ◽

Wei Wang ◽

Zhi Yuan

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Terminal Domain ◽

Carboxy Terminal Domain ◽

Beta Cyclodextrin ◽

Carboxy Terminal

Association between zinc(ii)-dipicolylamine appended beta-cyclodextrin and CTD (carboxy-terminal domain of RNA polymerase II) peptides with different phosphorylation patterns was studied by ITC and NMR.

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Carboxy-terminal domain of Cas differentially modulates c-Jun expression, DNA synthesis, and membrane ruffling induced by insulin, EGF, and IGF-1

Animal Cells and Systems ◽

10.1080/19768354.2018.1447013 ◽

2018 ◽

Vol 22 (2) ◽

pp. 69-75 ◽

Cited By ~ 1

Author(s):

Sun-Ju Yi ◽

Seong Yun Hwang ◽

Myung-ju Oh ◽

Kyunghwan Kim ◽

Byung H. Jhun

Keyword(s):

Dna Synthesis ◽

Membrane Ruffling ◽

Terminal Domain ◽

Carboxy Terminal Domain ◽

Carboxy Terminal

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The Carboxy-Terminal Tail of Human Cytomegalovirus (HCMV) US28 Regulates both Chemokine-Independent and Chemokine-Dependent Signaling in HCMV-Infected Cells

Journal of Virology ◽

10.1128/jvi.00354-09 ◽

2009 ◽

Vol 83 (19) ◽

pp. 10016-10027 ◽

Cited By ~ 24

Author(s):

Melissa P. Stropes ◽

Olivia D. Schneider ◽

William A. Zagorski ◽

Jeanette L. C. Miller ◽

William E. Miller

Keyword(s):

Human Cytomegalovirus ◽

Calcium Release ◽

Hcmv Infection ◽

Calcium Signal ◽

Terminal Domain ◽

Carboxy Terminal Domain ◽

Domain Truncation ◽

Infected Cells ◽

Heterologous Expression Systems ◽

Carboxy Terminal

ABSTRACT The human cytomegalovirus (HCMV)-encoded G-protein-coupled receptor (GPCR) US28 is a potent activator of a number of signaling pathways in HCMV-infected cells. The intracellular carboxy-terminal domain of US28 contains residues critical for the regulation of US28 signaling in heterologous expression systems; however, the role that this domain plays during HCMV infection remains unknown. For this study, we constructed an HCMV recombinant virus encoding a carboxy-terminal domain truncation mutant of US28, FLAG-US28/1-314, to investigate the role that this domain plays in US28 signaling. We demonstrate that US28/1-314 exhibits a more potent phospholipase C-β (PLC-β) signal than does wild-type US28, indicating that the carboxy-terminal domain plays an important role in regulating agonist-independent signaling in infected cells. Moreover, HMCV-infected cells expressing the US28/1-314 mutant exhibit a prolonged calcium signal in response to CCL5, indicating that the US28 carboxy-terminal domain also regulates agonist-dependent signaling. Finally, while the chemokine CX3CL1 behaves as an inverse agonist or inhibitor of constitutive US28 signaling to PLC-β, we demonstrate that CX3CL1 functions as an agonist with regard to US28-stimulated calcium release. This study is the first to demonstrate that the carboxy terminus of US28 controls US28 signaling in the context of HCMV infection and indicates that chemokines such as CX3CL1 can decrease constitutive US28 signals and yet simultaneously promote nonconstitutive US28 signals.

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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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