The Trypanosoma brucei TbHrg protein is a heme transporter involved in the regulation of stage-specific morphological transitions

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60077344%3A_____%2F17%3A00479119" target="_blank" >RIV/60077344:_____/17:00479119 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/61388971:_____/17:00479119 RIV/60076658:12310/17:43895458

Výsledek na webu

<a href="http://dx.doi.org/10.1074/jbc.M116.762997" target="_blank" >http://dx.doi.org/10.1074/jbc.M116.762997</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1074/jbc.M116.762997" target="_blank" >10.1074/jbc.M116.762997</a>

Jazyk výsledku

angličtina

Název v původním jazyce

The Trypanosoma brucei TbHrg protein is a heme transporter involved in the regulation of stage-specific morphological transitions

Popis výsledku v původním jazyce

The human parasite Trypanosoma brucei does not synthesize heme de novo and instead relies entirely on heme supplied by its vertebrate host or its insect vector, the tsetse fly. In the host bloodstream T. brucei scavenges heme via haptoglobin-hemoglobin (HpHb) receptor-mediated endocytosis occurring in the flagellar pocket. However, in the procyclic developmental stage, in which T. brucei is confined to the tsetse fly midgut, this receptor is apparently not expressed, suggesting that T. brucei takes up heme by a different, unknown route. To define this alternative route, we functionally characterized heme transporter TbHrg in the procyclic stage. RNAi-induced down-regulation of TbHrg in heme-limited culture conditions resulted in slower proliferation, decreased cellular heme, and marked changes in cellular morphology so that the cells resemble mesocyclic trypomastigotes. Nevertheless, the TbHrg KO developed normally in the tsetse flies at rates comparable with wild-type cells. T. brucei cells overexpressing TbHrg displayed up-regulation of the early procyclin GPEET and down-regulation of the late procyclin EP1, two proteins coating the T. brucei surface in the procyclic stage. Light microscopy of immunostained TbHrg indicated localization to the flagellar membrane, and scanning electron microscopy revealed more intense TbHrg accumulation toward the flagellar pocket. Based on these findings, we postulate that T. brucei senses heme levels via the flagellar TbHrg protein. Heme deprivation in the tsetse fly anterior midgut might represent an environmental stimulus involved in the transformation of this important human parasite, possibly through metabolic remodeling.

Název v anglickém jazyce

The Trypanosoma brucei TbHrg protein is a heme transporter involved in the regulation of stage-specific morphological transitions

Popis výsledku anglicky

The human parasite Trypanosoma brucei does not synthesize heme de novo and instead relies entirely on heme supplied by its vertebrate host or its insect vector, the tsetse fly. In the host bloodstream T. brucei scavenges heme via haptoglobin-hemoglobin (HpHb) receptor-mediated endocytosis occurring in the flagellar pocket. However, in the procyclic developmental stage, in which T. brucei is confined to the tsetse fly midgut, this receptor is apparently not expressed, suggesting that T. brucei takes up heme by a different, unknown route. To define this alternative route, we functionally characterized heme transporter TbHrg in the procyclic stage. RNAi-induced down-regulation of TbHrg in heme-limited culture conditions resulted in slower proliferation, decreased cellular heme, and marked changes in cellular morphology so that the cells resemble mesocyclic trypomastigotes. Nevertheless, the TbHrg KO developed normally in the tsetse flies at rates comparable with wild-type cells. T. brucei cells overexpressing TbHrg displayed up-regulation of the early procyclin GPEET and down-regulation of the late procyclin EP1, two proteins coating the T. brucei surface in the procyclic stage. Light microscopy of immunostained TbHrg indicated localization to the flagellar membrane, and scanning electron microscopy revealed more intense TbHrg accumulation toward the flagellar pocket. Based on these findings, we postulate that T. brucei senses heme levels via the flagellar TbHrg protein. Heme deprivation in the tsetse fly anterior midgut might represent an environmental stimulus involved in the transformation of this important human parasite, possibly through metabolic remodeling.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10608 - Biochemistry and molecular biology

Projekt

<a href="/cs/project/GA16-18699S" target="_blank" >GA16-18699S: Hem: potenciální hlavní regulátor u trypanosomatidů</a><br>

Návaznosti

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

Rok uplatnění

2017

Kód důvěrnosti údajů

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

Název periodika

Journal of Biological Chemistry

ISSN

0021-9258

e-ISSN

—

Svazek periodika

292

Číslo periodika v rámci svazku

17

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

13

Strana od-do

6998-7010

Kód UT WoS článku

000400478300012

EID výsledku v databázi Scopus

2-s2.0-85018346018