The genome of the early chordate Ciona intestinalis encodes only five cytoplasmic intermediate filament proteins including a single type I and type II keratin and a unique IF–annexin fusion protein

We screened the draft sequence of the human genome for genes that encode intermediate filament (IF) proteins in general, and keratins in particular. The draft covers nearly all previously established IF genes including the recent cDNA and gene additions, such as pancreatic keratin 23, synemin and the novel muscle protein syncoilin. In the draft, seven novel type II keratins were identified, presumably expressed in the hair follicle/epidermal appendages. In summary, 65 IF genes were detected, placing IF among the 100 largest gene families in humans. All functional keratin genes map to the two known keratin clusters on chromosomes 12 (type II plus keratin 18) and 17 (type I), whereas other IF genes are not clustered. Of the 208 keratin-related DNA sequences, only 49 reflect true keratin genes, whereas the majority describe inactive gene fragments and processed pseudogenes. Surprisingly, nearly 90% of these inactive genes relate specifically to the genes of keratins 8 and 18. Other keratin genes, as well as those that encode non-keratin IF proteins, lack either gene fragments/pseudogenes or have only a few derivatives. As parasitic derivatives of mature mRNAs, the processed pseudogenes of keratins 8 and 18 have invaded most chromosomes, often at several positions. We describe the limits of our analysis and discuss the striking unevenness of pseudogene derivation in the IF multigene family. Finally, we propose to extend the nomenclature of Moll and colleagues to any novel keratin.

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The amino acid sequence of component 7c, a type II intermediate-filament protein from wool

Biochemical Journal ◽

10.1042/bj2611015 ◽

1989 ◽

Vol 261 (3) ◽

pp. 1015-1022 ◽

Cited By ~ 26

Author(s):

L G Sparrow ◽

C P Robinson ◽

D T W McMahon ◽

M R Rubira

Keyword(s):

Amino Acid ◽

Amino Acid Sequence ◽

Intermediate Filament ◽

Coiled Coil ◽

British Library ◽

Intermediate Filament Protein ◽

Type I ◽

Type Ii ◽

Blocking Group ◽

Intermediate Filament Proteins

Component 7c is one of the four homologous type II intermediate-filament proteins that, by association with the complementary type I proteins, form the microfibrils or intermediate filaments in wool. Component 7c was isolated as the S-carboxymethyl derivative from Merino wool and its amino acid sequence was determined by manual and automatic sequencing of peptides produced by chemical and enzymic cleavage reactions. It is an N-terminally blocked molecule of 491 residues and Mr (not including the blocking group) of 55,600; the nature of the blocking group has not been determined. The predicted secondary structure shows that component 7c conforms to the now accepted pattern for intermediate-filament proteins in having a central rod-like region of approximately 310 residues of coiled-coil alpha-helix flanked by non-helical N-and C-terminal regions. The central region is divided by three non-coiled-coil linking segments into four helical segments 1A, 1B, 2A and 2B. The N-and C-terminal non-helical segments are 109 and 71 residues respectively and are rich in cysteine. Details of procedures use in determining the sequence of component 7c have been deposited as a Supplementary Publication SUP 50152 (65 pages) at the British Library Document Supply Centre, Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1989) 257,5. The information comprises: (1) details of chemical and enzymic methods used for cleavage of component 7c, peptides CN1, CN2 and CN3, and various other peptides, (2) details of the procedures used for the fractionation and purification of peptides from (1), including Figures showing the elution profiles from the chromatographic steps used, (3) details of methods used to determine the C-terminal sequence of peptide CN3, and (4) detailed evidence to justify a number of corrections to the previously published sequence.

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Split spinal cord malformations in children

Journal of Neurosurgery ◽

10.3171/jns.1998.88.1.0057 ◽

1998 ◽

Vol 88 (1) ◽

pp. 57-65 ◽

Cited By ~ 72

Author(s):

Yusuf Ersşahin ◽

Saffet Mutluer ◽

Sevgül Kocaman ◽

Eren Demirtasş

Keyword(s):

Spinal Cord ◽

Neurological Deficits ◽

Single Type ◽

Type I ◽

Type Ii ◽

Content Type ◽

Spinal Lesion ◽

The Mean ◽

Fine Print

Object. The authors reviewed and analyzed information on 74 patients with split spinal cord malformations (SSCMs) treated between January 1, 1980 and December 31, 1996 at their institution with the aim of defining and classifying the malformations according to the method of Pang, et al. Methods. Computerized tomography myelography was superior to other radiological tools in defining the type of SSCM. There were 46 girls (62%) and 28 boys (38%) ranging in age from less than 1 day to 12 years (mean 33.08 months). The mean age (43.2 months) of the patients who exhibited neurological deficits and orthopedic deformities was significantly older than those (8.2 months) without deficits (p = 0.003). Fifty-two patients had a single Type I and 18 patients a single Type II SSCM; four patients had composite SSCMs. Sixty-two patients had at least one associated spinal lesion that could lead to spinal cord tethering. After surgery, the majority of the patients remained stable and clinical improvement was observed in 18 patients. Conclusions. The classification of SSCMs proposed by Pang, et al., will eliminate the current chaos in terminology. In all SSCMs, either a rigid or a fibrous septum was found to transfix the spinal cord. There was at least one unrelated lesion that caused tethering of the spinal cord in 85% of the patients. The risk of neurological deficits resulting from SSCMs increases with the age of the patient; therefore, all patients should be surgically treated when diagnosed, especially before the development of orthopedic and neurological manifestations.

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Molecular characterization of an inward rectifier channel (IKir) found in avian vestibular hair cells: cloning and expression of pKir2.1

Physiological Genomics ◽

10.1152/physiolgenomics.00096.2004 ◽

2004 ◽

Vol 19 (2) ◽

pp. 155-169 ◽

Cited By ~ 11

Author(s):

Manning J. Correia ◽

Thomas G. Wood ◽

Deborah Prusak ◽

Tianxiang Weng ◽

Katherine J. Rennie ◽

...

Keyword(s):

Hair Cells ◽

Cho Cells ◽

Dwell Time ◽

Single Channel ◽

Cloning And Expression ◽

Single Type ◽

Type I ◽

Type Ii ◽

Vestibular Hair Cells ◽

Inwardly Rectifying

A fast inwardly rectifying current has been observed in some of the sensory cells (hair cells) of the inner ear of several species. While the current was presumed to be an IKir current, contradictory evidence existed as to whether the cloned channel actually belonged to the Kir2.0 subfamily of potassium inward rectifiers. In this paper, we report for the first time converging evidence from electrophysiological, biochemical, immunohistochemical, and genetic studies that show that the Kir2.1 channel carries the fast inwardly rectifying currents found in pigeon vestibular hair cells. Following cytoplasm extraction from single type II and multiple pigeon vestibular hair cells, mRNA was reverse transcribed, amplified, and sequenced. The open reading frame (ORF), consisting of a 1,284-bp nucleotide sequence, showed 94, 85, and 83% identity with Kir2.1 subunit sequences from chick lens, Kir2 sequences from human heart, and a mouse macrophage cell line, respectively. Phylogenetic analyses revealed that pKir2.1 formed an immediate node with hKir2.1 but not with hKir2.2–2.4. Hair cells (type I and type II) and supporting cells in the sensory epithelium reacted positively with a Kir2.1 antibody. The whole cell current recorded in oocytes and CHO cells, transfected with pigeon hair cell Kir2.1 (pKir2.1), demonstrated blockage by Ba2+ and sensitivity to changing K+ concentration. The mean single-channel linear slope conductance in transfected CHO cells was 29 pS. The open dwell time was long (∼300 ms at −100 mV), and the closed dwell time was short (∼34 ms at −100 mV). Multistates ranging from 3–6 were noted in some single-channel responses. All of the above features have been described for other Kir2.1 channels. Current clamp studies of native pigeon vestibular hair cells illustrated possible physiological roles of the channel and showed that blockage of the channel by Ba2+ depolarized the resting membrane potential by ∼30 mV. Negative currents hyperpolarized the membrane ∼20 mV before block but ∼60 mV following block. RT-PCR studies revealed that the pKir2.1 channels found in pigeon vestibular hair cells were also present in pigeon vestibular nerve, vestibular ganglion, lens, neck muscle, brain (brain stem, cerebellum and optic tectum), liver, and heart.

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Developmentally regulated cytokeratin gene in Xenopus laevis.

Molecular and Cellular Biology ◽

10.1128/mcb.5.10.2575 ◽

1985 ◽

Vol 5 (10) ◽

pp. 2575-2581 ◽

Cited By ~ 37

Author(s):

J A Winkles ◽

T D Sargent ◽

D A Parry ◽

E Jonas ◽

I B Dawid

Keyword(s):

Amino Acid ◽

Xenopus Laevis ◽

Intermediate Filament ◽

Type I ◽

Developmentally Regulated ◽

Amino Acid Homology ◽

Intermediate Filament Proteins ◽

Functional Roles ◽

Terminal Domain ◽

Terminal Domains

We have determined the sequence of cloned cDNAs derived from a 1,665-nucleotide mRNA which transiently accumulates during Xenopus laevis embryogenesis. Computer analysis of the deduced amino acid sequence revealed that this mRNA encodes a 47-kilodalton type I intermediate filament subunit, i.e., a cytokeratin. As is common to all intermediate filament subunits so far examined, the predicted polypeptide, named XK70, contains N- and C-terminal domains flanking a central alpha-helical rod domain. The overall amino acid homology between XK70 and a human 50-kilodalton type I keratin is 47%; homology within the alpha-helical domain is 57%. The N-terminal domain, which is not completely contained in our cDNAs, is basic, contains 42% serine plus alanine, and includes five copies of a six-amino-acid repeating unit. The C-terminal domain has a high alpha-helical content and contains a region with sequence homology to the C-terminal domains of other type I and type III intermediate filament proteins. We suggest that different keratin filament subtypes may have different functional roles during amphibian oogenesis and embryogenesis.

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Characterization of a recombinant type II 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase from Helicobacter pylori

Biochemical Journal ◽

10.1042/bj20050259 ◽

2005 ◽

Vol 390 (1) ◽

pp. 223-230 ◽

Cited By ~ 18

Author(s):

Celia J. Webby ◽

Mark L. Patchett ◽

Emily J. Parker

Keyword(s):

Helicobacter Pylori ◽

Sequence Similarity ◽

Condensation Reaction ◽

Enzyme Reaction ◽

Single Type ◽

Type I ◽

Type Ii ◽

Recombinant Type ◽

H Pylori ◽

Phosphate Synthase

DAH7P (3-Deoxy-D-arabino-heptulosonate 7-phosphate) synthase catalyses the condensation reaction between phosphoenolpyruvate (PEP) and D-erythrose 4-phosphate (E4P) as the first committed step in the biosynthesis of aromatic compounds in plants and micro-organisms. Previous work has identified two families of DAH7P synthases based on sequence similarity and molecular mass, with the majority of the mechanistic and structural studies being carried out on the type I paralogues from Escherichia coli. Whereas a number of organisms possess genes encoding both type I and type II DAH7P synthases, the pathogen Helicobacter pylori has only a single, type II, enzyme. Recombinant DAH7P synthase from H. pylori was partially solubilized by co-expression with chaperonins GroEL/GroES in E. coli, and purified to homogeneity. The enzyme reaction follows an ordered sequential mechanism with the following kinetic parameters: Km (PEP), 3 μM; Km (E4P), 6 μM; and kcat, 3.3 s−1. The enzyme reaction involves interaction of the si face of PEP with the re face of E4P. H. pylori DAH7P synthase is not inhibited by phenylalanine, tyrosine, tryptophan or chorismate. EDTA inactivates the enzyme, and activity is restored by a range of bivalent metal ions, including (in order of decreasing effectiveness) Co2+, Mn2+, Ca2+, Mg2+, Cu2+ and Zn2+. Analysis of type II DAH7P synthase sequences reveals several highly conserved motifs, and comparison with the type I enzymes suggests that catalysis by these two enzyme types occurs on a similar active-site scaffold and that the two DAH7P synthase families may indeed be distantly related.

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The Cloninger Type I/Type II Typology: Configurations and Personality Profiles in Socially Stable Alcohol Dependent Patients

Advances in Psychiatry ◽

10.1155/2014/346157 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Peter Wennberg ◽

Kristina Berglund ◽

Ulf Berggren ◽

Jan Balldin ◽

Claudia Fahlke

Keyword(s):

Longitudinal Study ◽

Alcohol Dependence ◽

Single Type ◽

Type I ◽

Type Ii ◽

Novelty Seeking ◽

Personality Profiles ◽

Study Population ◽

Males And Females ◽

Alcohol Dependent

Many attempts have been made to derive alcohol use typologies or subtypes of alcohol dependence and this study aimed at validating the type I/type II typology in a treatment sample of socially stable alcohol dependent males and females. A second aim was to compare the two types with respect to their temperament profiles. Data was part of a larger ongoing longitudinal study, the Gothenburg Alcohol Research Project, and included 269 alcohol dependent males and females recruited from three treatment centers. The results showed that type II alcoholism occurred as a more homogenous type than type I alcoholism, and type I alcoholism seemed too heterogeneous to be summarized into one single type. When adapting a strict classification, less than a third of the study population could be classified in accordance with the typology, suggesting that the typology is not applicable, at least in socially stable individuals with alcohol dependence. The results also showed that type II alcoholics showed higher levels of novelty seeking than did the individuals that were classified as type I alcoholics. Quite surprisingly, the individuals classified as type II alcoholics also showed higher levels of harm avoidance than did the individuals that were classified as type I alcoholics.

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Myoglobin concentration in single type I and type II muscle fibres in man

Histochemistry ◽

10.1007/bf00491118 ◽

1983 ◽

Vol 78 (1) ◽

pp. 121-124 ◽

Cited By ~ 19

Author(s):

E. Jansson ◽

C. Sylv�n

Keyword(s):

Single Type ◽

Muscle Fibres ◽

Type I ◽

Type Ii

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Seamless replacement of Autographa californica multiple nucleopolyhedrovirus gp64 with each of five novel type II alphabaculovirus fusion sequences generates pseudotyped virus that fails to transduce mammalian cells

Journal of General Virology ◽

10.1099/vir.0.041921-0 ◽

2012 ◽

Vol 93 (7) ◽

pp. 1583-1590

Author(s):

Marcel Westenberg ◽

Helen M. Soedling ◽

Nisha Hirani ◽

Linda J. Nicholson ◽

Derek A. Mann ◽

...

Keyword(s):

Gene Therapy ◽

Fusion Protein ◽

Autographa Californica ◽

Host Cells ◽

Type I ◽

Type Ii ◽

Cell Targeting ◽

Gene Therapy Vector ◽

Multiple Nucleopolyhedrovirus ◽

Hela Cell Lines

Autographa californica multiple nucleopolyhedrovirus (AcMNPV), a member of the type I alphabaculoviruses, is able to transduce and deliver a functional gene to a range of non-host cells, including many mammalian lines and primary cells, a property mediated by the envelope fusion protein GP64. AcMNPV is non-cytopathic and inherently replication deficient in non-host cells. As such, AcMNPV represents a possible new class of gene therapy vector with potential future clinical utility. Whilst not a problem for in vitro gene delivery, the broad tropism displayed for non-host cells is less desirable in a gene therapy vector. The fusion protein F of type II alphabaculoviruses can substitute functionally for GP64, and such pseudotyped viruses display a severely impaired capacity for non-host-cell transduction. Thus, surface decoration of such an F-pseudotyped AcMNPV with cell-binding ligands may restore transduction competence and generate vectors with desirable cell-targeting characteristics. By seamlessly swapping the native gp64 coding sequence with each of five sequences encoding different F proteins, a set of F-pseudotyped AcMNPV was generated. This report details their relative abilities both to functionally replace GP64 in viral growth and to transduce human Saos-2 and HeLa cells. All five supported viable infections in insect cell cultures and one, the Mamestra configurata NPV (MacoNPV) F pseudotype, could be amplified to titres close to those of native AcMNPV. In contrast, none was able to transduce the Saos-2 and HeLa cell lines. The robust support provided by MacoNPV F in virus production makes the corresponding pseudotype a viable scaffold to display surface ligands to direct selective mammalian cell targeting.

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Fiber type- and position-dependent expression of a myosin light chain-CAT transgene detected with a novel histochemical stain for CAT.

The Journal of Cell Biology ◽

10.1083/jcb.115.2.423 ◽

1991 ◽

Vol 115 (2) ◽

pp. 423-434 ◽

Cited By ~ 52

Author(s):

M J Donoghue ◽

J D Alvarez ◽

J P Merlie ◽

J R Sanes

Keyword(s):

Light Chain ◽

Transgene Expression ◽

Myosin Light Chain ◽

Fiber Type ◽

Muscle Fibers ◽

Single Type ◽

Regulatory Sequences ◽

Type I ◽

Type Ii ◽

Light Chain Gene

We recently generated and characterized transgenic mice in which regulatory sequences from a myosin light chain gene (MLC1f/3f) are linked to the chloramphenicol acetyltransferase (CAT) gene. Transgene expression in these mice is specific to skeletal muscle and graded along the rostrocaudal axis: adult muscles derived from successively more caudal somites express successively higher levels of CAT. To investigate the cellular basis of these patterns of expression, we developed and used a histochemical stain that allows detection of CAT in individual cells. Our main results are as follows: (a) Within muscles, CAT is detected only in muscle fibers and not in associated connective tissue, blood vessels, or nerves. Thus, the tissue specificity of transgene expression observed by biochemical assay reflects a cell-type specificity demonstrable histochemically. (b) Within individual muscles, CAT levels vary with fiber type. Like the endogenous MLC1f/3f gene, the transgene is expressed at higher levels in fast-twitch (type II) than in slow-twitch (type I) muscle fibers. In addition, CAT levels vary among type II fiber subtypes, in the order IIB greater than IIX greater than IIA. (c) Among muscles that are similar in fiber type composition, the average level of CAT per fiber varies with rostrocaudal position. This position-dependent variation in CAT level is apparent even when fibers of a single type are compared. From these results, we conclude that fiber type and position affect CAT expression independently. We therefore infer the existence of separate fiber type-specific and positionally graded transcriptional regulators that act together to determine levels of transgene expression.

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