scholarly journals Oligomerization of HEXIM1 via 7SK snRNA and coiled-coil region directs the inhibition of P-TEFb

2005 ◽  
Vol 33 (22) ◽  
pp. 7000-7010 ◽  
Author(s):  
D. Blazek
Keyword(s):  
Coiled Coil ◽  
Coiled Coil Region

scholarly journals A Coiled-Coil Domain of Melanophilin Is Essential for Myosin Va Recruitment and Melanosome Transport in Melanocytes

2006 ◽  
Vol 17 (11) ◽  
pp. 4720-4735 ◽  
Author(s):  
Alistair N. Hume ◽  
Abul K. Tarafder ◽  
José S. Ramalho ◽  
Elena V. Sviderskaya ◽  
Miguel C. Seabra
Keyword(s):  
Coiled Coil ◽  
Binding Domain ◽  
Actin Binding ◽  
Binding Studies ◽  
Null Cell ◽  
Coiled Coil Region ◽  
Actin Binding Domain ◽  
Transport Assay ◽  
Myosin Va

Melanophilin (Mlph) regulates retention of melanosomes at the peripheral actin cytoskeleton of melanocytes, a process essential for normal mammalian pigmentation. Mlph is proposed to be a modular protein binding the melanosome-associated protein Rab27a, Myosin Va (MyoVa), actin, and microtubule end-binding protein (EB1), via distinct N-terminal Rab27a-binding domain (R27BD), medial MyoVa-binding domain (MBD), and C-terminal actin-binding domain (ABD), respectively. We developed a novel melanosome transport assay using a Mlph-null cell line to study formation of the active Rab27a:Mlph:MyoVa complex. Recruitment of MyoVa to melanosomes correlated with rescue of melanosome transport and required intact R27BD together with MBD exon F–binding region (EFBD) and unexpectedly a potential coiled-coil forming sequence within ABD. In vitro binding studies indicate that the coiled-coil region enhances binding of MyoVa by Mlph MBD. Other regions of Mlph reported to interact with MyoVa globular tail, actin, or EB1 are not essential for melanosome transport rescue. The strict correlation between melanosomal MyoVa recruitment and rescue of melanosome distribution suggests that stable interaction with Mlph and MyoVa activation are nondissociable events. Our results highlight the importance of the coiled-coil region together with R27BD and EFBD regions of Mlph in the formation of the active melanosomal Rab27a-Mlph-MyoVa complex.

scholarly journals Over-Production, Crystallization, and Preliminary X-ray Crystallographic Analysis of a Coiled-Coil Region in Human Pericentrin

Crystals ◽  
2017 ◽  
Vol 7 (10) ◽  
pp. 296
Author(s):  
Min Kim ◽  
Jeong Park ◽  
Yeowon Sim ◽  
Doheum Kim ◽  
Jeong Sim ◽  
...  
Keyword(s):  
Coiled Coil ◽  
Crystallographic Analysis ◽  
X Ray ◽  
Coiled Coil Region

Identification of Proteins That Interact with the Central Coiled-Coil Region of the Human Protein Kinase NEK1†

Biochemistry ◽  
2003 ◽  
Vol 42 (51) ◽  
pp. 15369-15376 ◽  
Author(s):  
Marcelo J. Surpili ◽  
Tatiana M. Delben ◽  
Jörg Kobarg
Keyword(s):  
Protein Kinase ◽  
Coiled Coil ◽  
Human Protein ◽  
Human Protein Kinase ◽  
Coiled Coil Region

A novel natural mutation AαPhe98Ile in the fibrinogen coiled-coil affects fibrinogen function

2014 ◽  
Vol 111 (01) ◽  
pp. 79-87 ◽  
Author(s):  
Zuzana Riedelová-Reicheltová ◽  
Roman Kotlín ◽  
Jiří Suttnar ◽  
Věra Geierová ◽  
Tomáš Riedel ◽  
...  
Keyword(s):  
Platelet Aggregation ◽  
Coiled Coil ◽  
Fibrin Clot ◽  
Coiled Coil Region ◽  
Platelet Aggregometry ◽  
Sds Page ◽  
Lysis Rate ◽  
Thrombotic Complications ◽  
Natural Mutation ◽  
And Function

SummaryThe aim of this study was to investigate the structure and function of fibrinogen obtained from a patient with normal coagulation times and idiopathic thrombophilia. This was done by SDS-PAGE and DNA sequence analyses, scanning electron microscopy, fibrinopeptide release, fibrin polymerisation initiated by thrombin and reptilase, fibrinolysis, and platelet aggregometry. A novel heterozygous point mutation in the fibrinogen Aα chain, Phe98 to Ile, was found and designated as fibrinogen Vizovice. The mutation, which is located in the RGDF sequence (Aα 95–98) of the fibrinogen coiled-coil region, significantly affected fibrin clot morphology. Namely, the clot formed by fibrinogen Vizovice contained thinner and curled fibrin fibers with reduced length. Lysis of the clots prepared from Vizovice plasma and isolated fibrinogen were found to be impaired. The lysis rate of Vizovice clots was almost four times slower than the lysis rate of control clots. In the presence of platelets agonists the mutant fibrinogen caused increased platelet aggregation. The data obtained show that natural mutation of Phe98 to Ile in the fibrinogen Aα chain influences lateral aggregation of fibrin protofibrils, fibrinolysis, and platelet aggregation. They also suggest that delayed fibrinolysis, together with the abnormal fibrin network morphology and increased platelet aggregation, may be the direct cause of thrombotic complications in the patient associated with pregnancy loss.

scholarly journals Peroxisomes move by hitchhiking on early endosomes using the novel linker protein PxdA

2015 ◽  
Author(s):  
John Salogiannis ◽  
Martin J. Egan ◽  
Samara L. Reck-Peterson
Keyword(s):  
Molecular Motors ◽  
Intracellular Transport ◽  
Coiled Coil ◽  
Leading Edge ◽  
Time Lapse ◽  
Early Endosome ◽  
Organelle Transport ◽  
The Novel ◽  
Coiled Coil Region ◽  
Early Endosomes

Eukaryotic cells use microtubule-based intracellular transport for the delivery of many subcellular cargos, including organelles. The canonical view of organelle transport is that organelles directly recruit molecular motors via cargo-specific adaptors. In contrast to this view, we show here that peroxisomes move by hitchhiking on early endosomes, an organelle that directly recruits the transport machinery. Using the filamentous fungus Aspergillus nidulans we find that hitchhiking is mediated by a novel endosome-associated linker protein, PxdA. PxdA is required for normal distribution and long-range movement of peroxisomes, but not early endosomes or nuclei. Using simultaneous time-lapse imaging we find that early endosome-associated PxdA localizes to the leading edge of moving peroxisomes. We identify a coiled-coil region within PxdA that is necessary and sufficient for early endosome localization and peroxisome distribution and motility. These results present a new mechanism of microtubule-based organelle transport where peroxisomes hitchhike on early endosomes and identify PxdA as the novel linker protein required for this coupling.

scholarly journals Native chick laminin-4 containing the beta 2 chain (s-laminin) promotes motor axon growth.

1996 ◽  
Vol 135 (6) ◽  
pp. 1583-1592 ◽  
Author(s):  
R Brandenberger ◽  
R A Kammerer ◽  
J Engel ◽  
M Chiquet
Keyword(s):  
Basement Membrane ◽  
Neuromuscular Junction ◽  
Coiled Coil ◽  
Axon Growth ◽  
Motor Axon ◽  
Specific Sequence ◽  
Recombinant Fragment ◽  
Structural Context ◽  
Coiled Coil Region ◽  
Beta 2

After denervation of muscle, motor axons reinnervate original synaptic sites. A recombinant fragment of the synapse specific laminin beta 2 chain (s-laminin) was reported to inhibit motor axon growth. Consequently, a specific sequence (leucine-arginine-glutamate, LRE) of the laminin beta 2 chain was proposed to act as a stop signal and to mediate specific reinnervation at the neuromuscular junction (Porter, B.E., J. Weis, and J.R. Sanes. 1995. Neuron. 14:549-559). We demonstrate here that native chick laminin-4, which contains the beta 2 chain and is present in the synaptic basement membrane, does not inhibit but rather promotes motor axon growth. In native heterotrimeric laminin, the LRE sequence of the beta 2 chain is found in a triple coiled-coil region that is formed by all three subunits. We show here that the effect of LRE depends on the structural context. Whereas a recombinant randomly coiled LRE peptide indeed inhibited outgrowth by chick motoneurons, a small recombinant triple coiled-coil protein containing this sequence did not.

scholarly journals 2066 Functional characterization of mutant BRCA1

2018 ◽  
Vol 2 (S1) ◽  
pp. 13-13
Author(s):  
John Barrows ◽  
David Long
Keyword(s):  
Functional Characterization ◽  
Coiled Coil ◽  
Wild Type ◽  
Coiled Coil Region ◽  
Egg Extracts ◽  
Study Population ◽  
Xenopus Egg ◽  
Xenopus Egg Extracts

OBJECTIVES/SPECIFIC AIMS: The objective of this work is to determine the mechanistic consequences of BRCA1 mutants in inter-strand crosslink (ICL) repair. METHODS/STUDY POPULATION: Our lab uses Xenopus egg extracts to study ICL repair. These extracts can be depleted of endogenous BRCA1 by immunoprecipitation. The goal of this work is to rescue endogenous depletion with in vitro translated, wild type BRCA1. Once achieved, we can supplement the depleted extract with BRCA1 mutants to access their function in ICL repair. RESULTS/ANTICIPATED RESULTS: We hypothesize that the BRCT and RING domain mutations will abrogate ICL repair, while mutations in the coiled coil region will not affect repair. DISCUSSION/SIGNIFICANCE OF IMPACT: These findings will have an immense impact on the understanding of BRCA1 domains. Importantly these results will spur personalized therapy of BRCA1 mutants by showing which domains are sensitive to cross-linking agents.

scholarly journals Isolation and Characterization of EMILIN-2, a New Component of the Growing EMILINs Family and a Member of the EMI Domain-containing Superfamily

2001 ◽  
Vol 276 (15) ◽  
pp. 12003-12011 ◽  
Author(s):  
Roberto Doliana ◽  
Simonetta Bot ◽  
Gabriella Mungiguerra ◽  
Anna Canton ◽  
Stefano Paron Cilli ◽  
...  
Keyword(s):  
Elastic Fiber ◽  
Coiled Coil ◽  
Bac Clone ◽  
Protein Determination ◽  
Rich Domain ◽  
Isolation And Characterization ◽  
C Terminus ◽  
Coiled Coil Region ◽  
Novel Protein

EMILIN (elastinmicrofibrilinterfaselocated Protein) is an elastic fiber-associated glycoprotein consisting of a self-interacting globular C1q domain at the C terminus, a short collagenous stalk, an extended region of potential coiled-coil structure, and an N-terminal cysteine-rich domain (EMI domain). Using the globular C1q domain as a bait in the yeast two-hybrid system, we have isolated a cDNA encoding a novel protein. Determination of the entire primary structure demonstrated that this EMILIN-binding polypeptide is highly homologous to EMILIN. The domain organization is superimposable, one important difference being a proline-rich (41%) segment of 56 residues between the potential coiled-coil region and the collagenous domain absent in EMILIN. The entire gene (localized on chromosome 18p11.3) was isolated from a BAC clone, and it is structurally almost identical to that of EMILIN (8 exons, 7 introns with identical phases at the exon/intron boundaries) but much larger (about 40versus8 kilobases) than that of EMILIN. Given these findings we propose to name the novel protein EMILIN-2 and the prototype member of this family EMILIN-1 (formerly EMILIN). The mRNA expression of EMILIN-2 is more restricted compared with that of EMILIN-1; highest levels are present in fetal heart and adult lung, whereas, differently from EMILIN-1, adult aorta, small intestine, and appendix show very low expression, and adult uterus and fetal kidney are negative. Finally, the EMILIN-2 protein is secreted extracellularly byin vitro-grown cells, and in accordance with the partial coexpression in fetal and adult tissues, the two proteins shown extensive but not absolute immunocolocalizationin vitro.

Sign in / Sign up

Export Citation Format

Share Document