RiArsB and RiMT-11: Two novel genes induced by arsenate in arbuscular mycorrhiza

Ignacio E. Maldonado-Mendoza, Maria J. Harrison

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

© 2017 British Mycological Society. Plants associated with arbuscular mycorrhizal fungi (AMF) are capable of increasing their tolerance to arsenic (As)-polluted soils. However, the molecular mechanisms used by AMF to mediate this phenomenon are not well understood. The goal of this study is to investigate the genes involved in the AMF response to As pollution. Genes encoding proteins involved in As metabolism were identified using the available genomic/transcriptomic information of Rhizophagus irregularis (previously known as Glomus intraradices DAOM197198), and their expression assessed by either end-point PCR or real-time quantitative polymerase chain reaction (qPCR). Three genes, the previously characterized As-inducible gene GiArsA (R. irregularis ATP-binding cassette (ABC) ATPase component of the ArsAB arsenite efflux pump) and two new genes, an arsenate/arsenite permease component of ArsAB (RiArsB) and a methyltransferase type 11 (RiMT-11) were induced when exogenous arsenate was added to two-compartment in vitro monoxenic cultures of R. irregularis-transformed carrot roots. Next, we examined the expression of RiArsB and RiMT-11 in extraradical hyphae in response to arsenate. These genes displayed maximum induction 4-6 h after addition of 350 μM arsenate. Their expression was not restricted to extraradical mycelium, since their expression was also detected in colonized root tissues either grown in pots, or in the root-fungus compartment of two-compartment in vitro systems. We used a Medicago truncatula double mutant (mtpt4/mtpt8) to demonstrate that RiMT-11 and RiArsB transcripts accumulate in response to the addition of arsenate (as observed in extraradical hyphae in R. irregularis-colonized carrot root tissue) but not in response to phosphate, suggesting that these genes respond to arsenate addition regardless of nonfunctional Pi symbiotic transport. These results support the hypothesis that RiMT-11 may be involved in arsenate detoxification by methylation in AMF-colonized tissues.
Original languageAmerican English
JournalFungal Biology
DOIs
StatePublished - 1 Jan 2017

Fingerprint

Mycorrhizae
arbuscular mycorrhiza
arsenates
methyltransferases
Methyltransferases
arsenate
mycorrhizae
Arsenic
arsenic
gene
Fungi
mycorrhizal fungi
fungus
Genes
genes
arsenites
Daucus carota
Hyphae
arsenite
carrots

Cite this

@article{3f391ebfdbb549fa8c52d97f903cc216,
title = "RiArsB and RiMT-11: Two novel genes induced by arsenate in arbuscular mycorrhiza",
abstract = "{\circledC} 2017 British Mycological Society. Plants associated with arbuscular mycorrhizal fungi (AMF) are capable of increasing their tolerance to arsenic (As)-polluted soils. However, the molecular mechanisms used by AMF to mediate this phenomenon are not well understood. The goal of this study is to investigate the genes involved in the AMF response to As pollution. Genes encoding proteins involved in As metabolism were identified using the available genomic/transcriptomic information of Rhizophagus irregularis (previously known as Glomus intraradices DAOM197198), and their expression assessed by either end-point PCR or real-time quantitative polymerase chain reaction (qPCR). Three genes, the previously characterized As-inducible gene GiArsA (R. irregularis ATP-binding cassette (ABC) ATPase component of the ArsAB arsenite efflux pump) and two new genes, an arsenate/arsenite permease component of ArsAB (RiArsB) and a methyltransferase type 11 (RiMT-11) were induced when exogenous arsenate was added to two-compartment in vitro monoxenic cultures of R. irregularis-transformed carrot roots. Next, we examined the expression of RiArsB and RiMT-11 in extraradical hyphae in response to arsenate. These genes displayed maximum induction 4-6 h after addition of 350 μM arsenate. Their expression was not restricted to extraradical mycelium, since their expression was also detected in colonized root tissues either grown in pots, or in the root-fungus compartment of two-compartment in vitro systems. We used a Medicago truncatula double mutant (mtpt4/mtpt8) to demonstrate that RiMT-11 and RiArsB transcripts accumulate in response to the addition of arsenate (as observed in extraradical hyphae in R. irregularis-colonized carrot root tissue) but not in response to phosphate, suggesting that these genes respond to arsenate addition regardless of nonfunctional Pi symbiotic transport. These results support the hypothesis that RiMT-11 may be involved in arsenate detoxification by methylation in AMF-colonized tissues.",
author = "Maldonado-Mendoza, {Ignacio E.} and Harrison, {Maria J.}",
year = "2017",
month = "1",
day = "1",
doi = "10.1016/j.funbio.2017.11.003",
language = "American English",
journal = "Fungal Biology",
issn = "1878-6146",
publisher = "Elsevier",

}

RiArsB and RiMT-11: Two novel genes induced by arsenate in arbuscular mycorrhiza. / Maldonado-Mendoza, Ignacio E.; Harrison, Maria J.

In: Fungal Biology, 01.01.2017.

Research output: Contribution to journalArticle

TY - JOUR

T1 - RiArsB and RiMT-11: Two novel genes induced by arsenate in arbuscular mycorrhiza

AU - Maldonado-Mendoza, Ignacio E.

AU - Harrison, Maria J.

PY - 2017/1/1

Y1 - 2017/1/1

N2 - © 2017 British Mycological Society. Plants associated with arbuscular mycorrhizal fungi (AMF) are capable of increasing their tolerance to arsenic (As)-polluted soils. However, the molecular mechanisms used by AMF to mediate this phenomenon are not well understood. The goal of this study is to investigate the genes involved in the AMF response to As pollution. Genes encoding proteins involved in As metabolism were identified using the available genomic/transcriptomic information of Rhizophagus irregularis (previously known as Glomus intraradices DAOM197198), and their expression assessed by either end-point PCR or real-time quantitative polymerase chain reaction (qPCR). Three genes, the previously characterized As-inducible gene GiArsA (R. irregularis ATP-binding cassette (ABC) ATPase component of the ArsAB arsenite efflux pump) and two new genes, an arsenate/arsenite permease component of ArsAB (RiArsB) and a methyltransferase type 11 (RiMT-11) were induced when exogenous arsenate was added to two-compartment in vitro monoxenic cultures of R. irregularis-transformed carrot roots. Next, we examined the expression of RiArsB and RiMT-11 in extraradical hyphae in response to arsenate. These genes displayed maximum induction 4-6 h after addition of 350 μM arsenate. Their expression was not restricted to extraradical mycelium, since their expression was also detected in colonized root tissues either grown in pots, or in the root-fungus compartment of two-compartment in vitro systems. We used a Medicago truncatula double mutant (mtpt4/mtpt8) to demonstrate that RiMT-11 and RiArsB transcripts accumulate in response to the addition of arsenate (as observed in extraradical hyphae in R. irregularis-colonized carrot root tissue) but not in response to phosphate, suggesting that these genes respond to arsenate addition regardless of nonfunctional Pi symbiotic transport. These results support the hypothesis that RiMT-11 may be involved in arsenate detoxification by methylation in AMF-colonized tissues.

AB - © 2017 British Mycological Society. Plants associated with arbuscular mycorrhizal fungi (AMF) are capable of increasing their tolerance to arsenic (As)-polluted soils. However, the molecular mechanisms used by AMF to mediate this phenomenon are not well understood. The goal of this study is to investigate the genes involved in the AMF response to As pollution. Genes encoding proteins involved in As metabolism were identified using the available genomic/transcriptomic information of Rhizophagus irregularis (previously known as Glomus intraradices DAOM197198), and their expression assessed by either end-point PCR or real-time quantitative polymerase chain reaction (qPCR). Three genes, the previously characterized As-inducible gene GiArsA (R. irregularis ATP-binding cassette (ABC) ATPase component of the ArsAB arsenite efflux pump) and two new genes, an arsenate/arsenite permease component of ArsAB (RiArsB) and a methyltransferase type 11 (RiMT-11) were induced when exogenous arsenate was added to two-compartment in vitro monoxenic cultures of R. irregularis-transformed carrot roots. Next, we examined the expression of RiArsB and RiMT-11 in extraradical hyphae in response to arsenate. These genes displayed maximum induction 4-6 h after addition of 350 μM arsenate. Their expression was not restricted to extraradical mycelium, since their expression was also detected in colonized root tissues either grown in pots, or in the root-fungus compartment of two-compartment in vitro systems. We used a Medicago truncatula double mutant (mtpt4/mtpt8) to demonstrate that RiMT-11 and RiArsB transcripts accumulate in response to the addition of arsenate (as observed in extraradical hyphae in R. irregularis-colonized carrot root tissue) but not in response to phosphate, suggesting that these genes respond to arsenate addition regardless of nonfunctional Pi symbiotic transport. These results support the hypothesis that RiMT-11 may be involved in arsenate detoxification by methylation in AMF-colonized tissues.

U2 - 10.1016/j.funbio.2017.11.003

DO - 10.1016/j.funbio.2017.11.003

M3 - Article

C2 - 29458715

JO - Fungal Biology

JF - Fungal Biology

SN - 1878-6146

ER -