In vitro auxin treatment promotes cell division and delays endoreduplication in developing seeds of the model legume speciesMedicago truncatula

The increasing rate of fungal infections causes global problems not only in human healthcare but agriculture as well. To combat fungal pathogens limited numbers of antifungal agents are available therefore alternative drugs are needed. Antimicrobial peptides are potent candidates because of their broad activity spectrum and their diverse mode of actions. The model legume Medicago truncatula produces >700 nodule specific cysteine-rich (NCR) peptides in symbiosis and many of them have in vitro antimicrobial activities without considerable toxicity on human cells. In this work we demonstrate the anticandidal activity of the NCR335 and NCR169 peptide derivatives against five Candida species by using the micro-dilution method, measuring inhibition of biofilm formation with the XTT (2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide) assay, and assessing the morphological change of dimorphic Candida species by microscopy. We show that both the N- and C-terminal regions of NCR335 possess anticandidal activity as well as the C-terminal sequence of NCR169. The active peptides inhibit biofilm formation and the yeast-hypha transformation. Combined treatment of C. auris with peptides and fluconazole revealed synergistic interactions and reduced 2-8-fold the minimal inhibitory concentrations. Our results demonstrate that shortening NCR peptides can even enhance and broaden their anticandidal activity and therapeutic potential.

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Postpollination placental development of a diploid Solatium tuberosum

Canadian Journal of Botany ◽

10.1139/b88-247 ◽

1988 ◽

Vol 66 (9) ◽

pp. 1813-1817 ◽

Cited By ~ 4

Author(s):

A. Randall Olson

Keyword(s):

Solanum Tuberosum ◽

Cell Division ◽

Mitotic Activity ◽

Solanum Tuberosum L ◽

Cell Enlargement ◽

Placental Development ◽

Developing Seeds ◽

Solatium Tuberosum

Gynoecial placentation of Solanum tuberosum L. is axile with each parenchymatous placenta covered with numerous ovules. Three days after pollination, mitotic activity in the placental surface and subjacent layers initiates tissue proliferations, which develop between the ovules. Continued cell division and subsequent cell enlargement result in expanded placental projections, which separate the developing seeds from one another and form an interface with the inner pericarp within 10 – 12 days after pollination. Eventually, the placenta fills the remaining ovarian locular space and embeds the seeds.

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SpyAD, a Moonlighting Protein of Group A Streptococcus Contributing to Bacterial Division and Host Cell Adhesion

Infection and Immunity ◽

10.1128/iai.00064-14 ◽

2014 ◽

Vol 82 (7) ◽

pp. 2890-2901 ◽

Cited By ~ 11

Author(s):

Marilena Gallotta ◽

Giovanni Gancitano ◽

Giampiero Pietrocola ◽

Marirosa Mora ◽

Alfredo Pezzicoli ◽

...

Keyword(s):

Cell Division ◽

Mammalian Cells ◽

Group A Streptococcus ◽

Host Cells ◽

Knockout Mutant ◽

Content Type ◽

Moonlighting Protein ◽

Group A

ABSTRACTGroup A streptococcus (GAS) is a human pathogen causing a wide repertoire of mild and severe diseases for which no vaccine is yet available. We recently reported the identification of three protein antigens that in combination conferred wide protection against GAS infection in mice. Here we focused our attention on the characterization of one of these three antigens, Spy0269, a highly conserved, surface-exposed, and immunogenic protein of unknown function. Deletion of thespy0269gene in a GAS M1 isolate resulted in very long bacterial chains, which is indicative of an impaired capacity of the knockout mutant to properly divide. Confocal microscopy and immunoprecipitation experiments demonstrated that the protein was mainly localized at the cell septum and could interactin vitrowith the cell division protein FtsZ, leading us to hypothesize that Spy0269 is a member of the GAS divisome machinery. Predicted structural domains and sequence homologies with known streptococcal adhesins suggested that this antigen could also play a role in mediating GAS interaction with host cells. This hypothesis was confirmed by showing that recombinant Spy0269 could bind to mammalian epithelial cellsin vitroand thatLactococcus lactisexpressing Spy0269 on its cell surface could adhere to mammalian cellsin vitroand to mice nasal mucosain vivo. On the basis of these data, we believe that Spy0269 is involved both in bacterial cell division and in adhesion to host cells and we propose to rename this multifunctional moonlighting protein as SpyAD (StreptococcuspyogenesAdhesion andDivision protein).

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Cytokinesis and Midzone Microtubule Organization inCaenorhabditis elegans Require the Kinesin-like Protein ZEN-4

Molecular Biology of the Cell ◽

10.1091/mbc.9.8.2037 ◽

1998 ◽

Vol 9 (8) ◽

pp. 2037-2049 ◽

Cited By ~ 193

Author(s):

William B. Raich ◽

Adrienne N. Moran ◽

Joel H. Rothman ◽

Jeff Hardin

Keyword(s):

Cell Division ◽

Null Allele ◽

Time Lapse ◽

Equatorial Region ◽

Microtubule Organization ◽

Dividing Cells ◽

Spindle Midzone ◽

Cross Links ◽

Complete Cell

Members of the MKLP1 subfamily of kinesin motor proteins localize to the equatorial region of the spindle midzone and are capable of bundling antiparallel microtubules in vitro. Despite these intriguing characteristics, it is unclear what role these kinesins play in dividing cells, particularly within the context of a developing embryo. Here, we report the identification of a null allele ofzen-4, an MKLP1 homologue in the nematodeCaenorhabditis elegans, and demonstrate that ZEN-4 is essential for cytokinesis. Embryos deprived of ZEN-4 form multinucleate single-celled embryos as they continue to cycle through mitosis but fail to complete cell division. Initiation of the cytokinetic furrow occurs at the normal time and place, but furrow propagation halts prematurely. Time-lapse recordings and microtubule staining reveal that the cytokinesis defect is preceded by the dissociation of the midzone microtubules. We show that ZEN-4 protein localizes to the spindle midzone during anaphase and persists at the midbody region throughout cytokinesis. We propose that ZEN-4 directly cross-links the midzone microtubules and suggest that these microtubules are required for the completion of cytokinesis.

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Modification of cell division by phorbol ester in preimplantation mouse embryos

Development ◽

10.1242/dev.101.2.403 ◽

1987 ◽

Vol 101 (2) ◽

pp. 403-408

Author(s):

E.T. Mystkowska ◽

W. Sawicki

Keyword(s):

Cell Division ◽

Video Recording ◽

Mouse Embryos ◽

Time Intervals ◽

Cell Divisions ◽

Stage Of Development ◽

Preimplantation Mouse Embryos ◽

Preimplantation Mouse ◽

Single Blastomeres

2-cell mouse embryos were treated in vitro with a 2 h pulse of phorbol myristate acetate (PMA) at 32nd, 38th and 50th h after hCG, then chased in culture for up to 46 h. Embryos were fixed at various time intervals of chasing, then stained and inspected. Some embryos were carefully inspected with a video recording system, every 1.44s and the cell divisions (cytokinesis) as well as formation of large, single blastomeres, each from two smaller ones, were recorded. PMA pulse let to the suppression of cell divisions. The rate of the suppression was time dependent: with a delay of 0–1, 12 and 18 h between the PMA pulse and time of scheduled cell division about 99, 87 and 44% of 2-cell embryos remained at this stage of development, for at least 10 h, respectively, and 90, 58 and 12% of their blastomeres revealed binuclearity. Since we found that PMA-mediated formation of binuclearity was not the effect of cell fusions, it was assumed that the inhibition of cytokinesis preceded by karyokinesis was responsible for binuclearity. PMA effect on cell divisions was reversible. PMA-treated embryos revealed formation of large, single blastomeres, each from two smaller ones. If cell division appeared after PMA pulse, in about 52% of 3- to 6-cell embryos, the large blastomere formation was recorded in the course of the subsequent 38 h. Large blastomere formation was concluded to be the result of either cell fusion or reversion of incompleted cytokinesis brought about by PMA.

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Characterization and Expression Analysis of Genes Encoding Phosphoenolpyruvate Carboxylase and Phosphoenolpyruvate Carboxylase Kinase of Lotus japonicus, a Model Legume

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.2003.16.4.281 ◽

2003 ◽

Vol 16 (4) ◽

pp. 281-288 ◽

Cited By ~ 19

Author(s):

Tomomi Nakagawa ◽

Tomoko Izumi ◽

Mari Banba ◽

Yosuke Umehara ◽

Hiroshi Kouchi ◽

...

Keyword(s):

Phosphoenolpyruvate Carboxylase ◽

Root Nodules ◽

Expression Patterns ◽

Phosphorylation Site ◽

Lotus Japonicus ◽

Specific Protein ◽

Mrna Levels ◽

Model Legume ◽

Putative Phosphorylation Site

Phosphoenolpyruvate carboxylases (PEPCs), one form of which in each legume species plays a central role in the carbon metabolism in symbiotic root nodules, are activated through phosphorylation of a conserved residue by a specific protein kinase (PEPC-PK). We characterized the cDNAs for two PEPC isoforms of Lotus japonicus, an amide-translocating legume that forms determinate nodules. One gene encodes a nodule-enhanced form, which is more closely related to the PEPCs in amide-type indeterminate nodules than those in ureide-type determinate nodules. The other gene is expressed in shoots and roots at a low level. Both forms have the putative phosphorylation site, Ser11. We also isolated a cDNA and the corresponding genomic DNA for PEPC-PK of L. japonicus. The recombinant PEPC-PK protein expressed in Escherichia coli phosphorylated recombinant maize C4-form PEPC efficiently in vitro. The level of mRNA for PEPC-PK was high in root nodules, and those in shoots and roots were also significant. In situ hybridization revealed that the expression patterns of the transcripts for PEPC and PEPC-PK were similar in mature root nodules, but were different in emerging nodules. When L. japonicus seedlings were subjected to prolonged darkness and subsequent illumination, the activity of PEPC-PK and the mRNA levels of both PEPC and PEPC-PK in nodules decreased and then recovered, suggesting that they are regulated according to the amounts of photosynthates transported from shoots.

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Kinesin molecular motor Eg5 functions during polypeptide synthesis

Molecular Biology of the Cell ◽

10.1091/mbc.e11-03-0211 ◽

2011 ◽

Vol 22 (18) ◽

pp. 3420-3430 ◽

Cited By ~ 24

Author(s):

Kristen M. Bartoli ◽

Jelena Jakovljevic ◽

John L. Woolford ◽

William S. Saunders

Keyword(s):

Cell Division ◽

Molecular Motor ◽

Spindle Assembly ◽

Intact Cells ◽

Nascent Polypeptide ◽

Polypeptide Synthesis

The kinesin-related molecular motor Eg5 plays roles in cell division, promoting spindle assembly. We show that during interphase Eg5 is associated with ribosomes and is required for optimal nascent polypeptide synthesis. When Eg5 was inhibited, ribosomes no longer bound to microtubules in vitro, ribosome transit rates slowed, and polysomes accumulated in intact cells, suggesting defects in elongation or termination during polypeptide synthesis. These results demonstrate that the molecular motor Eg5 associates with ribosomes and enhances the efficiency of translation.

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