A single amino acid can switch the oligomerization state of the α-helical coiled-coil domain of cartilage matrix protein

The 2b protein of Pea early-browning virus (PEBV) is required for transmission of the virus by nematodes. Comparison of the 2b proteins of highly transmissible (TpA56) and poorly transmissible (SP5) isolates of PEBV identified two amino acid substitutions (G90S and G177R) that might be responsible for the poor transmission of isolate SP5. Hybrid viruses were created in which the TpA56 2b protein carried SP5-specific substitutions at residue 90 or 177, and in which the SP5 2b protein carried TpA56-specific substitutions at these positions. Transmission tests showed that the G177R substitution is sufficient to prevent nematode transmission of the virus. Examination of the 2b proteins from PEBV and other tobraviruses predicted the presence of a coiled-coil domain in the central region of the protein. This structural element is important for the association of interacting proteins and, thus, might mediate interaction of the 2b protein with the virus coat protein or with the vector nematode.

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A Single Amino Acid Substitution within a Coiled-coil Motif Changes the Assembly of a 53-Amino Acid Protein from Two-dimensional Sheets to Filamentous Structures

Journal of Biological Chemistry ◽

10.1074/jbc.m011296200 ◽

2001 ◽

Vol 276 (24) ◽

pp. 21250-21256 ◽

Cited By ~ 7

Author(s):

Alicia Bravo ◽

Gemma Serrano-Heras ◽

Margarita Salas

Keyword(s):

Amino Acid ◽

Amino Acid Substitution ◽

Coiled Coil ◽

Single Amino Acid Substitution ◽

Single Amino Acid ◽

Two Dimensional ◽

Acid Protein ◽

Amino Acid Protein

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Three differentially expressed survivin cDNA variants encode proteins with distinct antiapoptotic functions

Blood ◽

10.1182/blood.v95.4.1435.004k01_1435_1442 ◽

2000 ◽

Vol 95 (4) ◽

pp. 1435-1442 ◽

Cited By ~ 128

Author(s):

Edward M. Conway ◽

Saskia Pollefeyt ◽

Jan Cornelissen ◽

Inky DeBaere ◽

Marta Steiner-Mosonyi ◽

...

Keyword(s):

Amino Acid ◽

Amino Acid Residue ◽

Messenger Rna ◽

Coiled Coil ◽

Cdna Clones ◽

Exon 2 ◽

Reading Frame ◽

Coiled Coil Domain ◽

Acid Protein ◽

Apoptosis Protein

Survivin is a member of the inhibitor of apoptosis protein (IAP) family that is believed to play a role in oncogenesis. To elucidate further its physiologic role(s), we have characterized the murinesurvivin gene and complementary DNA (cDNA). The structural organization of the survivin gene, located on chromosome 11E2, is similar to that of its human counterpart, both containing 4 exons. Surprisingly, 3 full-length murine survivin cDNA clones were isolated, predicting the existence of 3 distinct survivin proteins. The longest open reading frame, derived from all 4 exons, predicts a 140-amino acid residue protein, survivin140, similar to human survivin, which contains a single IAP repeat and a COOH-terminal coiled-coil domain that links its function to the cell cycle. A second cDNA, which retains intron 3, predicts the existence of a 121-amino acid protein, survivin121 that lacks the coiled-coil domain. Removal of exon 2-derived sequences by alternative pre-messenger RNA (mRNA) splicing results in a third 40-amino acid residue protein, survivin40, lacking the IAP repeat and coiled-coil structure. Predictably, only recombinant survivin140 and survivin121 inhibited caspase-3 activity. All 3 mRNA species were variably expressed during development from 7.5 days postcoitum. Of the adult tissues surveyed, thymus and testis accumulated high levels of survivin140 mRNA, whereas survivin121-specific transcripts were detected in all tissues, while those representing survivin40 were absent. Human counterparts to the 3 survivin mRNA transcripts were identified in a study of human cells and tissues. The presence of distinct isoforms of survivin that are expressed differentially suggests that survivin plays a complex role in regulating apoptosis.

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Effects of single amino acid substitutions at the predicted coiled-coil or hydrophobic region on the self-assembly of ϕ29 replication protein, gp1

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2005.04.056 ◽

2005 ◽

Vol 331 (4) ◽

pp. 1310-1316 ◽

Cited By ~ 6

Author(s):

Kazuya Hashiyama ◽

Ari Takeuchi ◽

Osamu Makino

Keyword(s):

Amino Acid ◽

Self Assembly ◽

Coiled Coil ◽

The Self ◽

Replication Protein ◽

Single Amino Acid ◽

Amino Acid Substitutions ◽

Hydrophobic Region

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Structural studies on lamin. Similarities and differences between lamin and intermediate-filament proteins

Biochemical Journal ◽

10.1042/bj2380305 ◽

1986 ◽

Vol 238 (1) ◽

pp. 305-308 ◽

Cited By ~ 47

Author(s):

D A D Parry ◽

J F Conway ◽

P M Steinert

Keyword(s):

Amino Acid ◽

Coiled Coil ◽

Amino Acid Sequences ◽

Ionic Interactions ◽

Structural Studies ◽

Intermediate Filament Proteins ◽

Coiled Coil Domain ◽

Similarities And Differences ◽

Almost Continuous

Analysis of the amino acid sequences of lamins A and C has revealed that each chain has an almost continuous heptad-containing coiled-coil domain containing structural regularities in the linear disposition of the acidic and the basic residues. The data suggest that the lamin molecules are two-stranded ropes, that the two chains are parallel to one another and in axial register, and that the molecules aggregate in vivo through periodic ionic interactions. These results indicate that significant changes in stability of the nuclear envelope may be achieved between interphase and mitosis through changes in the degree of phosphorylation of the lamin proteins.

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Involvement of FtsE ATPase and FtsX Extracellular Loops 1 and 2 in FtsEX-PcsB Complex Function in Cell Division of Streptococcus pneumoniae D39

mBio ◽

10.1128/mbio.00431-13 ◽

2013 ◽

Vol 4 (4) ◽

Cited By ~ 28

Author(s):

Lok-To Sham ◽

Katelyn R. Jensen ◽

Kevin E. Bruce ◽

Malcolm E. Winkler

Keyword(s):

Signal Transduction ◽

Amino Acids ◽

Cell Division ◽

Streptococcus Pneumoniae ◽

Amino Acid ◽

Stationary Phase ◽

Coiled Coil ◽

Extracellular Loop ◽

Coiled Coil Domain ◽

Loop Domain

ABSTRACT The FtsEX protein complex has recently been proposed to play a major role in coordinating peptidoglycan (PG) remodeling by hydrolases with the division of bacterial cells. According to this model, cytoplasmic FtsE ATPase interacts with the FtsZ divisome and FtsX integral membrane protein and powers allosteric activation of an extracellular hydrolase interacting with FtsX. In the major human respiratory pathogen Streptococcus pneumoniae (pneumococcus), a large extracellular-loop domain of FtsX (ECL1FtsX) is thought to interact with the coiled-coil domain of the PcsB protein, which likely functions as a PG amidase or endopeptidase required for normal cell division. This paper provides evidence for two key tenets of this model. First, we show that FtsE protein is essential, that depletion of FtsE phenocopies cell defects caused by depletion of FtsX or PcsB, and that changes of conserved amino acids in the FtsE ATPase active site are not tolerated. Second, we show that temperature-sensitive (Ts) pcsB mutations resulting in amino acid changes in the PcsB coiled-coil domain (CCPcsB) are suppressed by ftsX mutations resulting in amino acid changes in the distal part of ECL1FtsX or in a second, small extracellular-loop domain (ECL2FtsX). Some FtsX suppressors are allele specific for changes in CCPcsB, and no FtsX suppressors were found for amino acid changes in the catalytic PcsB CHAP domain (CHAPPcsB). These results strongly support roles for both ECL1FtsX and ECL2FtsX in signal transduction to the coiled-coil domain of PcsB. Finally, we found that pcsB CC(Ts) mutants (Ts mutants carrying mutations in the region of pcsB corresponding to the coiled-coil domain) unexpectedly exhibit delayed stationary-phase autolysis at a permissive growth temperature. IMPORTANCE Little is known about how FtsX interacts with cognate PG hydrolases in any bacterium, besides that ECL1FtsX domains somehow interact with coiled-coil domains. This work used powerful genetic approaches to implicate a specific region of pneumococcal ECL1FtsX and the small ECL2FtsX in the interaction with CCPcsB. These findings identify amino acids important for in vivo signal transduction between FtsX and PcsB for the first time. This paper also supports the central hypothesis that signal transduction between pneumococcal FtsX and PcsB is linked to ATP hydrolysis by essential FtsE, which couples PG hydrolysis to cell division. The classical genetic approaches used here can be applied to dissect interactions of other integral membrane proteins involved in PG biosynthesis. Finally, delayed autolysis of the pcsB CC(Ts) mutants suggests that the FtsEX-PcsB PG hydrolase may generate a signal in the PG necessary for activation of the major LytA autolysin as pneumococcal cells enter stationary phase.

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Characterization of Two New Imatinib-Responsive Fusion Genes Generated by Disruption of PDGFRB in Eosinophilia-Associated Chronic Myeloproliferative Disorders.

Blood ◽

10.1182/blood.v108.11.667.667 ◽

2006 ◽

Vol 108 (11) ◽

pp. 667-667

Author(s):

Christoph Walz ◽

Georgia Metzgeroth ◽

Claudia Schoch ◽

Torsten Haferlach ◽

Rudiger Hehlmann ◽

...

Keyword(s):

Amino Acid ◽

Fusion Protein ◽

Tyrosine Kinase ◽

Coiled Coil ◽

Myeloproliferative Disorders ◽

Fusion Genes ◽

Protein Protein Interaction ◽

Coiled Coil Domain ◽

Exon 11

Abstract Fusion genes involving PDGFRA, PDGFRB, FGFR1 and JAK2 are seen in a substantial number of patients with BCR-ABL negative myeloproliferative disorders (MPD) and result in constitutive activation of the corresponding tyrosine kinase moiety. The vast majority of tyrosine kinase fusion partners contain coiled-coil domains or other dimerization motifs properties that are essential for malignant transformation. We have identified two patients presenting with eosinophilia-associated MPD and a t(5;12)(q31;q24) or a complex translocation t(1;5;11) with involvement of 5q31, respectively, suggesting a possible involvement of the PDGFRB gene which is located at chromosome band 5q31–33. 5′-rapid amplification of cDNA ends (5′-RACE) for the t(5;12) identified an in-frame mRNA fusion between ’G protein-coupled receptor kinase interactor 2′ (GIT2) exon 12 at 12q24 and PDGFRB exon 11. GIT2 is a member of the GIT protein family that is extensively alternative spliced in many distinct forms causing its functional diversity. A reciprocal transcript was amplified by RT-PCR with a fusion between PDGFRB exon 10 and GIT2 exon 13. GIT2-PDGFRB is predicted to be translated into a 742 amino acid fusion protein that retains the GIT2 N-terminal protein-protein interaction motif Ankyrin and an Arf GTPase activating protein (ArfGAP) domain fused to the transmembrane and catalytic domain of PDGFRB. The truncated GIT2 protein lacks coiled-coil domains as they are lost in the fusion protein due to the breakpoint within GIT2 intron 12. We therefore speculate that the Ankyrin repeat, which is one of the most common protein-protein interaction motifs in nature, may have replaced the function of a coiled-coil domain offering dimerization properties to the fusion protein. 5′-RACE for the complex t(1;5;11) identified an in-frame mRNA fusion between ’GPI-anchored membrane protein 1′ (GPIAP1) exon 7 at 11p13 and PDGFRB exon 11. Normal GPIAP1 is a cytoplasmic phosphoprotein which plays a mainly uncharacterized role in cellular activation or proliferation. The chimeric mRNA is predicted to encode an 803 amino acid fusion protein retaining the coiled-coil domain of GPIAP1 fused to the transmembrane and catalytic domains of PDGFRB. Both patients have been treated with 400 mg/day imatinib, which is a selective inhibitor of PDGFRB, and achieved rapid complete clinical and hematological remission. Residual GIT2-PDGFRB transcripts could be detected repeatedly during a 17 months follow up in case 1 whereas no follow-up samples have been available for case 2. These data give further evidence that numerous partner genes fuse to PDGFRB in BCR-ABL negative MPDs. In addition, the data demonstrate that cytogenetic analysis is a mandatory technique for the identification of tyrosine kinase fusion genes. In cases with abnormalities of chromosome 5q, a possible involvement of PDGFRB should be screened by adequate FISH and PCR-based techniques. Although their occurrence is rare in general, the identification of these fusion genes is essential for the successful treatment with tyrosine kinase inhibitors.

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