multiple stressor effects of ionising (gamma) radiation ...€¦ · multiple stressor effects of...

Multiple stressor effects of ionising (gamma) radiation and non-ionising (UV)

radiation in duckweed (Lemna minor)

Li Xie1,2,3, You Song1,3, Knut Asbjørn Solhaug2,3, Ole Christian Lind2,3, Brit

Salbu2,3, Bjørn Johnsen4, Knut Erik Tollefsen1,2,3

1 Norwegian Institute for Water Research (NIVA)

2 Faculty of Environmental Sciences and Natural Resource Management (MINA), Norway Norwegian

University of Life Sciences (NMBU)

3Centre for Environmental Radioactivity (CERAD), Norwegian University of Life Sciences (NMBU)

4Norwegian Radiation protection Authorty (NRPA)

Contact : [email protected]

LI XIE

LI XIE

10 -14

10 -12

10 -10

10 -8

10 -6

10 -4

10 -2

1 10 2

10 4

10 6

Wavelength in Meters

Broadcast

Short wave TV

FM

Radar Infrared

Near Far

Visible

Ultraviolet

X Rays

Gamma Rays

Cosmic Rays

Ionizing Radiation Nonionizing Radiation

INTRO

DU

CTIO

N

M&

M

RESU

LTS

CO

NCLU

SIO

N

Ionizing and Non-Ionizing radiation

LI XIE

What will happen in

the aquatic ecosystem?

Additivity

(1+1=2)

Antagonism

(1+1<2)

Synergy

(1+1>2)

INTRO

DU

CTIO

N

M&

M

RESU

LTS

CO

NCLU

SIO

N

The challenge

LI XIE

Central function in aquatic ecosystems

Easily cultured in controlled laboratory conditions

Standardised protocols available for regulatory testing

Rapid reproduction capacity

Highly sensitive to contaminants

Genome partly sequenced, molecular tools partly available

INTRO

DU

CTIO

N

M&

M

RESU

LTS

CO

NCLU

SIO

N

Duckweeds (Lemna minor)

LI XIE

Stressor Molecular Initiating

Event

Key Events

Adverse

Outcome

Population effect

Clarify the individual and combine effect of -radiation and UVR in the duckweed

Study

Develop adverse outcome pathway (AOP) framework

Modeling

Hazard Assessment Application

INTRO

DU

CTIO

N

M&

M

RESU

LTS

CO

NCLU

SIO

N

Objective

LI XIE

Endpoints:

Growth

ROS formation

Lipid peroxidation

OXPHOS

PSII efficiency

Pigments

DNA damage

Gene expression

Gamma dose rate

DWater (mGy/h)*

Gamma total dose

DWater (mGy)

UV

Dose rate

(W/m2)

13.2 2195

0.5±0.03 20.3 3375

47.1 7831

Study 1: UV radiation effects Study 2: Gamma radiation effects

Study 3: UV and gamma radiation combined effects

60Co

60Co

UV Chamber

Two-way ANOVA

Statistics

INTRO

DU

CTIO

N

M&

M

RESU

LTS

CO

NCLU

SIO

N

Approach

LI XIE

INTRO

DU

CTIO

N

M&

M

RESU

LTS

CO

NCLU

SIO

N

Growth

UV did not interrupt gamma radiation effects on frond size and

weight but reproduction rate.

-ra d ia t io n ra te (m G y /h )

Re

pro

du

cti

on

In

hib

itio

n

(%)

0 1 3 .2 2 0 .3 4 7 .1

-1 0

0

1 0

2 0

3 0

4 0

U V -

U V +* *

bb

a ba

b

aa

c

*


Fro

nd

siz

e i

nh

ibit

on

(%

)

0 1 3 .2 2 0 .3 4 7 .1

-5

0

5

1 0

1 5

2 0

U V -

U V +

b b

a b

a

b

a b

a

b


Fre

sh

we

igh

t in

hib

itio

n (

%)

0 1 3 .2 2 0 .3 4 7 .1

-1 0

0

1 0

2 0

3 0

U V -

U V +

b

b

a b

a

b c

a b

a

c

Reproduction Frond size Frond weight

LI XIE

Activation

antioxidant

defense system

INTRO

DU

CTIO

N

M&

M

RESU

LTS

CO

NCLU

SIO

N

Oxidative stress


RO

S (

Fo

ld I

nc

re

as

e)

0 1 3 .2 2 0 .3 4 7 .1

0 .0

0 .5

1 .0

1 .5

2 .0

U V -

U V +

b

b

a b

a

b

b

a

a

*

*

-ra d ia t io n ra te (m G y /h )L

PO

(F

old

In

cre

as

e)

0 1 3 .2 2 0 .3 4 7 .1

0 .0

0 .5

1 .0

1 .5

2 .0

U V -

U V +

a

a

a

a

cb

aa

*

ROS formation Lipid peroxidation

LI XIE

ROS

INTRO

DU

CTIO

N

M&

M

RESU

LTS

CO

NCLU

SIO

N

Oxidative phosphorylation


MM

P (

Fo

ld I

nc

re

as

e)

0 1 3 .2 2 0 .3 4 7 .1

0 .6

0 .7

0 .8

0 .9

1 .0

1 .1

1 .2

U V -

U V +a

aa

b

a

a ba b

b

**

*

*

Mitochondrial membrane

potential

UVR reduced MMP and interfere gamma radiation effect

LI XIE

RO

S

INTRO

DU

CTIO

N

M&

M

RESU

LTS

CO

NCLU

SIO

N

PS II inhibition


Fv

/Fm

(F

old

In

cre

as

e)

0 1 2 2 0 4 0

0 .7

0 .8

0 .9

1 .0

1 .1

U V -

U V +a

aa

b

bc

c

a

*

**

*


ET

R (

Fo

ld I

nc

re

as

e)

0 1 2 2 0 4 0

0 .7

0 .8

0 .9

1 .0

1 .1

U V -

U V +

aa

aa

a

a b

b

a

*


NP

Q (

Fo

ld I

nc

re

as

e)

0 1 2 2 0 4 0

0 .0

0 .5

1 .0

1 .5

2 .0

U V -

U V +

b

a b aa

d

b

a

c

*

*

Maximal PS II efficiency Electron transport rate Non-photochemical

quenching

In combined exposure, -radiation and UV had additive effects on

Fv/Fm

LI XIE

ROS

INTRO

DU

CTIO

N

M&

M

RESU

LTS

CO

NCLU

SIO

N

Pigment content


Ch

la

+b

(F

old

In

cre

as

e)

0 1 3 .2 2 0 .3 4 7 .1

0 .0

0 .5

1 .0

1 .5

U V -

U V +

a a a

a

a a aa


Ca

ro

ten

oid

s

(Fo

ld I

nc

re

as

e)

0 1 3 .2 2 0 .3 4 7 .1

0 .0

0 .5

1 .0

1 .5

2 .0

U V -

U V +

c

b

a

b

a a

aa

* *

*

Total chlorophyll Total carotenoids

Carotenoids are also

antioxidants to quenching

ROS in plant

LI XIE

Stressor Molecular initiating

Event

Key Events

Individual effect

Population effect

PSII efficiency Growth Population trajectories

Pigment

destruction

ROS

ETR blocking

NPQ increase

?

OXPHOS

PSII efficiency Growth

INTRO

DU

CTIO

N

M&

M

RESU

LTS

CO

NCLU

SIO

N

LI XIE

http://footage.framepool.com

THANK YOU!

[email protected]

Tânia Gomes

You Song

Dag Brede

Dag Wenner

Hans Christian Teien

Yetneberk Ayalew Kassaye

Terje Christensen

multiple stressor effects of ionising (gamma) radiation ...€¦ · multiple stressor effects of...

Documents