Role of the TFG N-terminus and coiled-coil domain in the transforming activity of the thyroid TRK-T3 oncogene

TMEM120A (Transmembrane protein 120A) was recently identified as a mechanical pain sensing ion channel named as TACAN, while its homologue TMEM120B has no mechanosensing property1. Here, we report the cryo-EM structures of both human TMEM120A and TMEM120B. The two structures share the same dimeric assembly, mediated by extensive interactions through the transmembrane domain (TMD) and the N-terminal coiled coil domain (CCD). However, the nearly identical structures cannot provide clues for the difference in mechanosensing between TMEM120A and TMEM120B. Although TMEM120A could mediate conducting currents in a bilayer system, it does not mediate mechanical-induced currents in a heterologous expression system, suggesting TMEM120A is unlikely a mechanosensing channel. Instead, the TMDs of TMEM120A and TMEM120B resemble the structure of a fatty acid elongase, ELOVL7, indicating their potential role of an enzyme in lipid metabolism.

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Expression in Escherichia coli of fragments of the coiled-coil rod domain of rabbit myosin: influence of different regions of the molecule on aggregation and paracrystal formation

Journal of Cell Science ◽

10.1242/jcs.99.4.823 ◽

1991 ◽

Vol 99 (4) ◽

pp. 823-836

Author(s):

S.J. Atkinson ◽

M. Stewart

Keyword(s):

Escherichia Coli ◽

Ionic Strength ◽

Coiled Coil ◽

Periodic Variation ◽

Heptad Repeat ◽

C Terminus ◽

N Terminus ◽

Low Ionic Strength ◽

Myosin Rod

We have expressed in Escherichia coli a cDNA clone corresponding broadly to rabbit light meromyosin (LMM) together with a number of modified polypeptides and have used this material to investigate the role of different aspects of molecular structure on the solubility properties of LMM. The expressed material was characterized biochemically and structurally to ensure that it retained the coiled-coil conformation of the native molecule. Full-length recombinant LMM retained the general solubility properties of myosin and, although soluble at high ionic strength, precipitated when the ionic strength was reduced below 0.3 M. Constructs in which the ‘skip’ residues (that disrupt the coiled-coil heptad repeat) were deleted had solubility properties indistinguishable from the wild type, which indicated that the skip residues did not play a major role in determining the molecular interactions involved in assembly. Deletions from the N terminus of LMM did not alter the solubility properties of the expressed material, but deletion of 92 residues from the C terminus caused a large increase in solubility at low ionic strength, indicating that a determinant important for interaction between LMM molecules was located in this region. The failure of deletions from the molecule's N terminus to alter its solubility radically suggested that the periodic variation of charge along the myosin rod may not be as important as proposed for determining the strength of binding between molecules and thus the solubility of myosin.

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N-terminal targeting of guanine nucleotide exchange factors (GEF) for ADP ribosylation factors (ARF) to the Golgi

Journal of Cell Science ◽

10.1242/jcs.113.11.1883 ◽

2000 ◽

Vol 113 (11) ◽

pp. 1883-1889 ◽

Cited By ~ 5

Author(s):

S.Y. Lee ◽

B. Pohajdak

Keyword(s):

Coiled Coil ◽

Guanine Nucleotide ◽

Nucleotide Exchange ◽

Ph Domain ◽

Adp Ribosylation ◽

Guanine Nucleotide Exchange ◽

Coiled Coil Domain ◽

Nucleotide Exchange Factor ◽

N Terminus ◽

Point Mutagenesis

B2-1 (cytohesin-1) is a member of a group of proteins (including ARNO and ARNO3) that are all of similar size and domain composition. The three proteins contain an N-terminal coiled-coil domain, followed by a Sec7 and a pleckstrin homology (PH) domain. While it is well established that the Sec7 domain functions as a guanine nucleotide exchange factor (GEF) for ADP-ribosylation factors (ARFs) and the PH domain anchors the proteins to membrane phosphoinositols, the function of the N-terminal domain is unknown. Here we show that the N terminus of B2-1 (residues 1–54) is necessary and sufficient to target the protein to the Golgi. The Sec7+PH domains of B2-1 (residues 55–398) are not sufficient for Golgi localization. Further deletion analysis and point mutagenesis indicate that the coiled-coil domain within the N terminus is responsible for Golgi targeting. Furthermore, ARNO and ARNO3 N termini also have the same capability of targeting to the Golgi. We conclude that the N-terminal, (α)-helical, coiled-coil domain is used to target this family of proteins to the Golgi complex.

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Role of TFG sequences outside the coiled-coil domain in TRK-T3 oncogenic activation

Oncogene ◽

10.1038/sj.onc.1206189 ◽

2003 ◽

Vol 22 (6) ◽

pp. 807-818 ◽

Cited By ~ 20

Author(s):

Emanuela Roccato ◽

Sonia Pagliardini ◽

Loredana Cleris ◽

Silvana Canevari ◽

Franca Formelli ◽

...

Keyword(s):

Coiled Coil ◽

Coiled Coil Domain

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Dimerization of the ATRIP Protein through the Coiled-Coil Motif and Its Implication to the Maintenance of Stalled Replication Forks

Molecular Biology of the Cell ◽

10.1091/mbc.e05-05-0427 ◽

2005 ◽

Vol 16 (12) ◽

pp. 5551-5562 ◽

Cited By ~ 26

Author(s):

Eisuke Itakura ◽

Isao Sawada ◽

Akira Matsuura

Keyword(s):

Mammalian Cells ◽

Coiled Coil ◽

Genotoxic Stress ◽

Replication Forks ◽

Cycle Arrest ◽

Coiled Coil Domain ◽

Functional Complex ◽

Stalled Replication Forks

ATR (ATM and Rad3-related), a PI kinase-related kinase (PIKK), has been implicated in the DNA structure checkpoint in mammalian cells. ATR associates with its partner protein ATRIP to form a functional complex in the nucleus. In this study, we investigated the role of the ATRIP coiled-coil domain in ATR-mediated processes. The coiled-coil domain of human ATRIP contributes to self-dimerization in vivo, which is important for the stable translocation of the ATR-ATRIP complex to nuclear foci that are formed after exposure to genotoxic stress. The expression of dimerization-defective ATRIP diminishes the maintenance of replication forks during treatment with replication inhibitors. By contrast, it does not compromise the G2/M checkpoint after IR-induced DNA damage. These results show that there are two critical functions of ATR-ATRIP after the exposure to genotoxic stress: maintenance of the integrity of replication machinery and execution of cell cycle arrest, which are separable and are achieved via distinct mechanisms. The former function may involve the concentrated localization of ATR to damaged sites for which the ATRIP coiled-coil motif is critical.

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Phosphorylation of Serine 114 on Atg32 mediates mitophagy

Molecular Biology of the Cell ◽

10.1091/mbc.e11-02-0145 ◽

2011 ◽

Vol 22 (17) ◽

pp. 3206-3217 ◽

Cited By ~ 127

Author(s):

Yoshimasa Aoki ◽

Tomotake Kanki ◽

Yuko Hirota ◽

Yusuke Kurihara ◽

Tetsu Saigusa ◽

...

Keyword(s):

Signal Transduction ◽

Quality Control ◽

Significant Role ◽

Coiled Coil ◽

Adaptor Protein ◽

Mitochondrial Quality Control ◽

Signal Transduction Cascade ◽

Coiled Coil Domain ◽

C Terminus ◽

N Terminus

Mitophagy, which selectively degrades mitochondria via autophagy, has a significant role in mitochondrial quality control. When mitophagy is induced in yeast, mitochondrial residential protein Atg32 binds Atg11, an adaptor protein for selective types of autophagy, and it is recruited into the vacuole along with mitochondria. The Atg11–Atg32 interaction is believed to be the initial molecular step in which the autophagic machinery recognizes mitochondria as a cargo, although how this interaction is mediated is poorly understood. Therefore, we studied the Atg11–Atg32 interaction in detail. We found that the C-terminus region of Atg11, which included the fourth coiled-coil domain, interacted with the N-terminus region of Atg32 (residues 100–120). When mitophagy was induced, Ser-114 and Ser-119 on Atg32 were phosphorylated, and then the phosphorylation of Atg32, especially phosphorylation of Ser-114 on Atg32, mediated the Atg11–Atg32 interaction and mitophagy. These findings suggest that cells can regulate the amount of mitochondria, or select specific mitochondria (damaged or aged) that are degraded by mitophagy, by controlling the activity and/or localization of the kinase that phosphorylates Atg32. We also found that Hog1 and Pbs2, which are involved in the osmoregulatory signal transduction cascade, are related to Atg32 phosphorylation and mitophagy.

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A stutter in the coiled coil domain of E.coli co-chaperone GrpE connects structure with function

10.1101/2020.07.03.186056 ◽

2020 ◽

Author(s):

Tulsi Upadhyay ◽

Vaibhav V Karekar ◽

Ishu Saraogi

Keyword(s):

Heat Stress ◽

Coiled Coil ◽

Bacterial Survival ◽

Nucleotide Exchange ◽

E Coli ◽

Coiled Coil Domain ◽

Nucleotide Exchange Factor ◽

First Time

AbstractIn bacteria, the co-chaperone GrpE acts as a nucleotide exchange factor and plays an important role in controlling the chaperone cycle of DnaK. The functional form of GrpE is an asymmetric dimer, consisting of a long non-ideal coiled-coil. During heat stress, this region partially unfolds and prevents DnaK nucleotide exchange, ultimately ceasing the chaperone cycle. In this study, we elucidate the role of thermal unfolding of the coiled-coil domain of E. coli GrpE in regulating its co-chaperonic activity. The presence of a stutter disrupts the regular heptad arrangement typically found in an ideal coiled coil resulting in structural distortion. Introduction of hydrophobic residues at the stutter altered the structural stability of the coiled-coil. Using an in vitro FRET assay, we show for the first time that the enhanced stability of GrpE resulted in an increased affinity for DnaK. However, the mutants were defective in in vitro functional assays, and were unable to support bacterial growth at heat shock temperature in a grpE-deleted E. coli strain. This work provides valuable insights into the functional role of a stutter in the GrpE coiled-coil, and its role in regulating the DnaK-chaperone cycle for bacterial survival during heat stress. More generally, our findings illustrate how a sequence specific stutter in a coiled-coil domain regulates the structure function trade-off in proteins.

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Dual Regulatory Roles of the Extended N Terminus for Activation of the Tomato Mi-1.2 Resistance Protein

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-11-11-0302 ◽

2012 ◽

Vol 25 (8) ◽

pp. 1045-1057 ◽

Cited By ~ 20

Author(s):

Ewa Lukasik-Shreepaathy ◽

Erik Slootweg ◽

Hanna Richter ◽

Aska Goverse ◽

Ben J. C. Cornelissen ◽

...

Keyword(s):

Cell Death ◽

Coiled Coil ◽

Terminal Region ◽

Regulatory Function ◽

Cell Death Response ◽

N Terminus ◽

Positive Regulators ◽

In Trans ◽

Lrr Protein

Plant resistance (R) proteins mediate race-specific immunity and initiate host defenses that are often accompanied by a localized cell-death response. Most R proteins belong to the nucleotide binding-leucine-rich repeat (NB-LRR) protein family, as they carry a central NB-ARC domain fused to an LRR domain. The coiled-coil (CC) domain at the N terminus of some solanaceous NB-LRR proteins is extended with a solanaceae domain (SD). Tomato Mi-1.2, which confers resistance against nematodes, white flies, psyllids, and aphids, encodes a typical SD-CNL protein. Here, we analyzed the role of the extended N terminus for Mi-1.2 activation. Removal of the first part of the N terminus (Nt1) induced Mi-1.2-mediated cell death that could be suppressed by overexpression of the second half of the N-terminal region. Yet, autoactivating NB-ARC-LRR mutants require in trans coexpression of the N-terminal region to induce cell death, indicating that the N terminus functions both as a negative and as a positive regulator. Based on secondary structure predictions, we could link both activities to three distinct subdomains, a typical CC domain and two novel, structurally-conserved helical subdomains called SD1 and SD2. A negative regulatory function could be assigned to the SD1, whereas SD2 and the CC together function as positive regulators of Mi-1.2-mediated cell death.

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