Absence of a conventional spindle mitotic checkpoint in the binucleated single-celled parasite Giardia intestinalis

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F16%3A10325106" target="_blank" >RIV/00216208:11310/16:10325106 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216208:11110/16:10325106

Výsledek na webu

<a href="http://dx.doi.org/10.1016/j.ejcb.2016.07.003" target="_blank" >http://dx.doi.org/10.1016/j.ejcb.2016.07.003</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ejcb.2016.07.003" target="_blank" >10.1016/j.ejcb.2016.07.003</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Absence of a conventional spindle mitotic checkpoint in the binucleated single-celled parasite Giardia intestinalis

Popis výsledku v původním jazyce

The spindle assembly checkpoint (SAC) joins the machinery of chromosome-to-spindle microtubule attachment with that of the cell cycle to prevent missegregation of chromosomes during mitosis. Although a functioning SAC has been verified in a limited number of organisms, it is regarded as an evolutionarily conserved safeguard mechanism. In this report, we focus on the existence of the SAC in a single-celled parasitic eukaryote, Giardia intestinalis. Giardia belongs to Excavata, a large and diverse supergroup of unicellular eukaryotes in which SAC control has been nearly unexplored. We show that Giardia cells with absent or defective mitotic spindles due to the inhibitory effects of microtubule poisons do not arrest in mitosis; instead, they divide without any delay, enter the subsequent cell cycle and even reduplicate DNA before dying. We identified a limited repertoire of kinetochore and SAC components in the Giardia genome, indicating that this parasite is ill equipped to halt mitosis before the onset of anaphase via SAC control of chromosome-spindle microtubule attachment. Finally, based on overexpression, we show that Giardia Mad2, a core SAC protein in other eukaryotes, localizes along intracytoplasmic portions of caudal flagellar axonemes, but never within nuclei, even in mitotic cells with blocked spindles, where the SAC should be active. These findings are consistent with the absence of a conventional SAC, known from yeast and metazoans, in the parasitic protist Giardia.

Název v anglickém jazyce

Absence of a conventional spindle mitotic checkpoint in the binucleated single-celled parasite Giardia intestinalis

Popis výsledku anglicky

The spindle assembly checkpoint (SAC) joins the machinery of chromosome-to-spindle microtubule attachment with that of the cell cycle to prevent missegregation of chromosomes during mitosis. Although a functioning SAC has been verified in a limited number of organisms, it is regarded as an evolutionarily conserved safeguard mechanism. In this report, we focus on the existence of the SAC in a single-celled parasitic eukaryote, Giardia intestinalis. Giardia belongs to Excavata, a large and diverse supergroup of unicellular eukaryotes in which SAC control has been nearly unexplored. We show that Giardia cells with absent or defective mitotic spindles due to the inhibitory effects of microtubule poisons do not arrest in mitosis; instead, they divide without any delay, enter the subsequent cell cycle and even reduplicate DNA before dying. We identified a limited repertoire of kinetochore and SAC components in the Giardia genome, indicating that this parasite is ill equipped to halt mitosis before the onset of anaphase via SAC control of chromosome-spindle microtubule attachment. Finally, based on overexpression, we show that Giardia Mad2, a core SAC protein in other eukaryotes, localizes along intracytoplasmic portions of caudal flagellar axonemes, but never within nuclei, even in mitotic cells with blocked spindles, where the SAC should be active. These findings are consistent with the absence of a conventional SAC, known from yeast and metazoans, in the parasitic protist Giardia.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

EA - Morfologické obory a cytologie

OECD FORD obor

—

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2016

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

European Journal of Cell Biology

ISSN

0171-9335

e-ISSN

—

Svazek periodika

95

Číslo periodika v rámci svazku

10

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

13

Strana od-do

355-367

Kód UT WoS článku

000385322700001

EID výsledku v databázi Scopus

2-s2.0-84990038871