CP250, a Novel Acidic Coiled Coil Protein of the Dictyostelium centrosome, Affects Growth, Chemotaxis, and the Nuclear Envelope

Rosemarie Blau-Wasser; Ursula Euteneuer; Huajiang Xiong; Berthold Gassen; Michael Schleicher; Angelika A. Noegel

doi:10.1091/mbc.e09-03-0180

CP250, a Novel Acidic Coiled Coil Protein of the Dictyostelium centrosome, Affects Growth, Chemotaxis, and the Nuclear Envelope

Molecular Biology of the Cell ◽

10.1091/mbc.e09-03-0180 ◽

2009 ◽

Vol 20 (20) ◽

pp. 4348-4361 ◽

Cited By ~ 16

Author(s):

Rosemarie Blau-Wasser ◽

Ursula Euteneuer ◽

Huajiang Xiong ◽

Berthold Gassen ◽

Michael Schleicher ◽

...

Keyword(s):

Amino Acids ◽

Nuclear Envelope ◽

Envelope Protein ◽

Amorphous Matrix ◽

Coiled Coil ◽

Size Growth ◽

Pericentriolar Material ◽

Late Telophase ◽

Cycle Dependent ◽

Mutant Cells

The Dictyostelium centrosome is a nucleus associated body consisting of a box-shaped core surrounded by the corona, an amorphous matrix functionally equivalent to the pericentriolar material of animal centrosomes which is responsible for the nucleation and anchoring of microtubules. Here we describe CP250 a component of the corona, an acidic coiled coil protein that is present at the centrosome throughout interphase while disappearing during prophase and reappearing at the end of late telophase. Amino acids 756-1148 of the 2110 amino acids are sufficient for centrosomal targeting and cell cycle–dependent centrosome association. Mutant cells lacking CP250 are smaller in size, growth on bacteria is delayed, chemotaxis is altered, and development is affected, which, in general, are defects observed in cytoskeletal mutants. Furthermore, loss of CP250 affected the nuclear envelope and led to reduced amounts and altered distribution of Sun-1, a conserved nuclear envelope protein that connects the centrosome to chromatin.

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Identification of a 102 kDa protein (cytocentrin) immunologically related to keratin 19, which is a cytoplasmically derived component of the mitotic spindle pole

Journal of Cell Science ◽

10.1242/jcs.106.3.967 ◽

1993 ◽

Vol 106 (3) ◽

pp. 967-981 ◽

Cited By ~ 5

Author(s):

E.C. Paul ◽

A. Quaroni

Keyword(s):

Cellular Localization ◽

Spindle Pole ◽

Early Prophase ◽

Mitotic Apparatus ◽

Nuclear Envelope Breakdown ◽

Keratin 19 ◽

Pericentriolar Material ◽

Late Telophase ◽

Cytoplasmic Microtubules ◽

Cycle Dependent

The mAb RK7, previously shown to recognize keratin 19, was also found to cross-react with a biologically unrelated 102 kDa protein, which becomes associated with the poles of the mitotic apparatus. This newly identified protein, called cytocentrin, is a stable cellular component, may be at least in part phosphorylated, and displays a cell cycle-dependent cellular localization. In interphase cells, it is diffusely distributed in the cytosol and shows no affinity for cytoplasmic microtubules. It becomes localized to the centrosome in early prophase, prior to nuclear envelope breakdown, separation of replicated centrosomes, and nucleation of mitotic apparatus microtubules. During metaphase, cytocentrin is located predominately at the mitotic poles, often appearing as an aggregate of small globular sub-components; it also associates with some polar microtubules. In late anaphase/early telophase cytocentrin dissociates entirely from the mitotic apparatus and becomes temporarily localized with microtubules in the midbody, from which it disappears by late telophase. In taxol-treated cells cytocentrin was associated with the center of the miniasters but also showed affinity for some cytoplasmic microtubules. Studies employing G2-synchronized cells and nocodazole demonstrated that cytocentrin can become associated with mitotic centrosomes independently of tubulin polymerization and that microtubules regrow from antigen-containing foci. We interpret these results to suggest that cytocentrin is a cytoplasmic protein that becomes specifically activated or modified at the onset of mitosis so that it can affiliate with the mitotic poles where it may provide a link between the pericentriolar material and other components of the mitotic apparatus.

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The plant nuclear envelope protein MAF1 has an additional location at the Golgi and binds to a novel Golgi-associated coiled-coil protein

Planta ◽

10.1007/s00425-005-0076-0 ◽

2005 ◽

Vol 222 (6) ◽

pp. 1028-1040 ◽

Cited By ~ 4

Author(s):

Shalaka Patel ◽

Jelena Brkljacic ◽

Frank Gindullis ◽

Annkatrin Rose ◽

Iris Meier

Keyword(s):

Nuclear Envelope ◽

Envelope Protein ◽

Coiled Coil

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Faculty Opinions recommendation of Comparative genomics in Chlamydomonas and Plasmodium identifies an ancient nuclear envelope protein family essential for sexual reproduction in protists, fungi, plants, and vertebrates.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718205928.793488517 ◽

2013 ◽

Author(s):

Joseph Heitman

Keyword(s):

Comparative Genomics ◽

Nuclear Envelope ◽

Sexual Reproduction ◽

Envelope Protein ◽

Protein Family

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Faculty Opinions recommendation of System analysis shows distinct mechanisms and common principles of nuclear envelope protein dynamics.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.9899960.10614054 ◽

2011 ◽

Author(s):

Markus Engstler ◽

Manfred Alsheimer

Keyword(s):

Nuclear Envelope ◽

Protein Dynamics ◽

Envelope Protein ◽

System Analysis

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Mutational analyses of fs(1)Ya, an essential, developmentally regulated, nuclear envelope protein in Drosophila.

Genetics ◽

10.1093/genetics/141.4.1473 ◽

1995 ◽

Vol 141 (4) ◽

pp. 1473-1481 ◽

Cited By ~ 1

Author(s):

J Liu ◽

K Song ◽

M F Wolfner

Keyword(s):

Cell Cycle ◽

Embryonic Development ◽

Nuclear Envelope ◽

Envelope Protein ◽

Chromatin Condensation ◽

Cell Cycle Control ◽

Nuclear Lamina ◽

Mitotic Division ◽

Developmentally Regulated ◽

Egg Maturation

Abstract The fs(1)Ya protein (YA) is an essential, maternally encoded, nuclear lamina protein that is under both developmental and cell cycle control. A strong Ya mutation results in early arrest of embryos. To define the function of YA in the nuclear envelope during early embryonic development, we characterized the phenotypes of four Ya mutants alleles and determined their molecular lesions. Ya mutant embryos arrest with abnormal nuclear envelopes prior to the first mitotic division; a proportion of embryos from two leaky Ya mutants proceed beyond this but arrest after several abnormal divisions. Ya unfertilized eggs contain nuclei of different sizes and condensation states, apparently due to abnormal fusion of the meiotic products immediately after meiosis. Lamin is localized at the periphery of the uncondensed nuclei in these eggs. These results suggest that YA function is required during and after egg maturation to facilitate proper chromatin condensation, rather than to allow a lamin-containing nuclear envelope to form. Two leaky Ya alleles that partially complement have lesions at opposite ends of the YA protein, suggesting that the N- and C-termini are important for YA function and that YA might interact with itself either directly or indirectly.

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The key amino acids of E protein involved in early flavivirus infection: viral entry

Virology Journal ◽

10.1186/s12985-021-01611-2 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Tao Hu ◽

Zhen Wu ◽

Shaoxiong Wu ◽

Shun Chen ◽

Anchun Cheng

Keyword(s):

Amino Acids ◽

Conformational Changes ◽

Viral Entry ◽

Envelope Protein ◽

Cell Attachment ◽

Envelope Proteins ◽

Infection Process ◽

Early Infection ◽

Protein Amino Acids ◽

Α Helix

AbstractFlaviviruses are enveloped viruses that infect multiple hosts. Envelope proteins are the outermost proteins in the structure of flaviviruses and mediate viral infection. Studies indicate that flaviviruses mainly use envelope proteins to bind to cell attachment receptors and endocytic receptors for the entry step. Here, we present current findings regarding key envelope protein amino acids that participate in the flavivirus early infection process. Among these sites, most are located in special positions of the protein structure, such as the α-helix in the stem region and the hinge region between domains I and II, motifs that potentially affect the interaction between different domains. Some of these sites are located in positions involved in conformational changes in envelope proteins. In summary, we summarize and discuss the key envelope protein residues that affect the entry process of flaviviruses, including the process of their discovery and the mechanisms that affect early infection.

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The Xenopus protein kinase pEg2 associates with the centrosome in a cell cycle-dependent manner, binds to the spindle microtubules and is involved in bipolar mitotic spindle assembly

Journal of Cell Science ◽

10.1242/jcs.111.5.557 ◽

1998 ◽

Vol 111 (5) ◽

pp. 557-572 ◽

Cited By ~ 19

Author(s):

C. Roghi ◽

R. Giet ◽

R. Uzbekov ◽

N. Morin ◽

I. Chartrain ◽

...

Keyword(s):

Cell Cycle ◽

Protein Kinase ◽

Mitotic Spindle ◽

Cultured Cells ◽

Dependent Manner ◽

Egg Extracts ◽

Pericentriolar Material ◽

Spindle Microtubules ◽

Cycle Dependent

By differential screening of a Xenopus laevis egg cDNA library, we have isolated a 2,111 bp cDNA which corresponds to a maternal mRNA specifically deadenylated after fertilisation. This cDNA, called Eg2, encodes a 407 amino acid protein kinase. The pEg2 sequence shows significant identity with members of a new protein kinase sub-family which includes Aurora from Drosophila and Ipl1 (increase in ploidy-1) from budding yeast, enzymes involved in centrosome migration and chromosome segregation, respectively. A single 46 kDa polypeptide, which corresponds to the deduced molecular mass of pEg2, is immunodetected in Xenopus oocyte and egg extracts, as well as in lysates of Xenopus XL2 cultured cells. In XL2 cells, pEg2 is immunodetected only in S, G2 and M phases of the cell cycle, where it always localises to the centrosomal region of the cell. In addition, pEg2 ‘invades’ the microtubules at the poles of the mitotic spindle in metaphase and anaphase. Immunoelectron microscopy experiments show that pEg2 is located precisely around the pericentriolar material in prophase and on the spindle microtubules in anaphase. We also demonstrate that pEg2 binds directly to taxol stabilised microtubules in vitro. In addition, we show that the presence of microtubules during mitosis is not necessary for an association between pEg2 and the centrosome. Finally we show that a catalytically inactive pEg2 kinase stops the assembly of bipolar mitotic spindles in Xenopus egg extracts.

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Sequence and expression of the dCMP deaminase gene (DCD1) of Saccharomyces cerevisiae

Molecular and Cellular Biology ◽

10.1128/mcb.6.5.1711-1721.1986 ◽

1986 ◽

Vol 6 (5) ◽

pp. 1711-1721

Author(s):

E M McIntosh ◽

R H Haynes

Keyword(s):

Saccharomyces Cerevisiae ◽

Amino Acids ◽

Amino Acid ◽

Amino Acid Sequences ◽

Open Reading Frame ◽

Northern Analysis ◽

Hindiii Site ◽

Reading Frame ◽

Hindiii Restriction Site ◽

Cycle Dependent

The dCMP deaminase gene (DCD1) of Saccharomyces cerevisiae has been isolated by screening a Sau3A clone bank for complementation of the dUMP auxotrophy exhibited by dcd1 dmp1 haploids. Plasmid pDC3, containing a 7-kilobase (kb) Sau3A insert, restores dCMP deaminase activity to dcd1 mutants and leads to an average 17.5-fold overproduction of the enzyme in wild-type cells. The complementing activity of the plasmid was localized to a 4.2-kb PvuII restriction fragment within the Sau3A insert. Subcloning experiments demonstrated that a single HindIII restriction site within this fragment lies within the DCD1 gene. Subsequent DNA sequence analysis revealed a 936-nucleotide open reading frame encompassing this HindIII site. Disruption of the open reading frame by integrative transformation led to a loss of enzyme activity and confirmed that this region constitutes the dCMP deaminase gene. Northern analysis indicated that the DCD1 mRNA is a 1.15-kb poly(A)+ transcript. The 5' end of the transcript was mapped by primer extension and appears to exhibit heterogeneous termini. Comparison of the amino acid sequence of the T2 bacteriophage dCMP deaminase with that deduced for the yeast enzyme revealed a limited degree of homology which extends over the entire length of the phage polypeptide (188 amino acids) but is confined to the carboxy-terminal half of the yeast protein (312 amino acids). A potential dTTP-binding site in the yeast and phage enzymes was identified by comparison of homologous regions with the amino acid sequences of a variety of other dTTP-binding enzymes. Despite the role of dCMP deaminase in dTTP biosynthesis, Northern analysis revealed that the DCD1 gene is not subject to the same cell cycle-dependent pattern of transcription recently found for the yeast thymidylate synthetase gene (TMP1).

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