Plants Interacting

with Pathogens

Walter Gassmann

The cellular basis of plant immunity

J L Dangl et al. Science 2013;341:746-751Published by AAAS

PAMP-triggered

immunity

Effector-

triggered

immunity

The IPG plant-microbe interactome (simplified)

Brown

English

Gassmann

Heese

Koo

Korkin

Mihail

Mitchum

Peck

Schoelz

Stacey

Zhang

Tools

genetics/genomics

molecular biology

biochemistry

cell biology

spectrometry

computational biology

Process

PTI

ETI

pathogenicity

hormones

regulation

Plant

Arabidopsis

soybean

Nicotiana

other

Microbe

bacteria

fungi

viruses

nematodes

other

The IPG plant-microbe interactome (simplified)

Brown

English

Gassmann

Heese

Koo

Korkin

Mihail

Mitchum

Peck

Schoelz

Stacey

Zhang

Tools

genetics/genomics

molecular biology

biochemistry

cell biology

spectrometry

computational biology

Process

PTI

ETI

pathogenicity

hormones

regulation

Plant

Arabidopsis

soybean

Nicotiana

other

Microbe

bacteria

fungi

viruses

nematodes

other

What is the mechanism underlying polar growth of Agrobacterium tumefaciens?

Polar attachment of Agrobacterium tumefaciens cells to a root hair

Crown gall tumor caused by Agrobacterium tumefaciens

The Brown lab (brown.biology.missouri.edu) is interested in understanding the mechanism of polar elongation in Agrobacterium tumefaciens

New growth (unlabeled) of the Agrobacterium tumefaciens cell occurs at the cell pole

We expect to apply insights gained from this basic research to address:

- the need for biocontrol of this plant pathogen - for improved genetic engineering of plants

Pam Brown

1. P6 forms inclusion bodies that are considered “virion factories”. Almost all CaMV virions are retained with the P6 inclusion bodies.

EM of P6 inclusion body adjacent to chloroplast

2. P6 inclusion bodies interact with and move on actin

microfilaments. Harries et al. 2009, Plant Phys.

P6 protein tagged with GFP.Actin tagged with dsRed

3. P6 protein physically interacts with CHUP1, a protein that moves

chloroplasts on microfilaments. Angel et al. 2013, Virology.

CHUP1, tagged with CFP, is localized to the outer membrane of chloroplasts, which autofluoresce red

CaMV P6 is a multifunctional protein, with distinct roles in translation of viral proteins, silencing suppression, defense gene suppression, and trafficking of CaMV virions to plasmodesmata.

Jim Schoelz

FLS2

?

How Does PAMP RecognitionLead to Host Resitance?

??

0 min 8 min2 min

388.1

535.1

633.2

672.2

770.3

100 200 300 400 500 600 700 800

m/z

yΔ6438.2

272.0

y1

175.4

y6

y5

y2

510.5461.9

b3b2251.0

I H H P P pS P R

y5 y4 y3 y2 y1y6

b2 b3

yΔ5

yΔ4

yΔ3

yΔn= yn – H3PO4

y3

Scott Peck

High Affinity (~1 nM) Chitin and Lipo-Chitin Signaling Pathways in Plants

X

Symbiotic NF receptor

Chitin

Chitooctaose receptor

X

Non-symbiotic NF receptor

ALL PLANTS SYMBIOTIC PLANTS

Induction of plant

defense pathways

Suppression of

plant innate

immunity

Induction of

symbiotic

development

Gary

Stacey

How Do Cyst Nematodes Reprogram Host Cells?

Mitchum et al (2012) Annu Rev Phyto Melissa Mitchum

DGA

CytoplasmicEffectors

RCR3ApoplasticEffectors

β-1,3-G

SPS Hs10A06 Hg/Hs30C02

GrVAP

Ma Gro1-4 Hero A Gpa2 Cf-2Mi9Mi-1.2

GpRBP1

GrSPRYSEC19

MiCRT

Rhg4SHMT

Hs1Pro-1

Rhg1

α-SNAP WI12AAT

WRKY72

WRKY70

Basal Defense

NB

TIR

TM

CC

LRR

GrCEP12

Nucleus

HSP90

Mechanisms of Plant Resistance to Nematodes

Liu, Kandoth et al., Nature (2012) 492: 256-260

Kandoth & Mitchum, COPB (2013) 16: 457-463

Jasmonate Metabolism and Signaling

Plant resistance to various biotic stresses are controlled by lipid-derived hormone jasmonate. Metabolic processes involved in maintenance of optimal hormone level as well as its control over global gene expression are studied using multidisciplinary approaches including mass spectrometry.

UPLC-MS/MS

Abraham Koo

Constitutively activated immunity is deleterious to

the plant

Columbia-0 srfr1-4

SRFR1 encodes a novel TPR protein

that may function as an adaptor protein

TPR

srfr1-1 srfr1-2

"conserved domain of

unknown function"

1052 aa

AtSRFR1MtOsDdEhHsTTC13MmTnSpCeOGT1DmOGTAtSECAtSPYScSSN6AtSGT1b

SRFR1-

like

TPR

TGAATG7400*

srfr1-1

*srfr1-2

GFP-SRFR1 + RFP

TCP

TF

promoterdefense gene

Kim et al., unpublished

SRFR1 is a nucleocytoplasmic adaptor protein that

negatively regulates the plant immune system

TNL

TNLRPS6

AvrRps4

immunity

HopA1

EDS1RPS4SNC1

SRFR1

Bhattacharjee et al. (2011) Science

Nimchuck et al. (2003) Annu. Rev. Gen. 37: 579

adapted from Tao et al. (2003) Plant Cell 15: 317

SRFR1 may determine the sensitivity of the plant

effector-triggered immune response

srfr1

The cellular basis of plant immunity

J L Dangl et al. Science 2013;341:746-751Published by AAAS

PAMP-triggered

immunity

Effector-

triggered

immunity

AcknowledgmentsGassmann lab:

Sang Hee Kim

Fei Gao

Sharon Pike

Morgan Halane

Chris Garner

Ben Spears

Ellie Nguyen

Courtney Coleman

Ru Dai

Yang Liu

Saikat Bhattacharjee, Regional

Centre for Biotech, India

Daniel Nam, Texas State

Xuecheng Zhang, MU

Soon Il Kwon, Korea Univ.

Jessica Koczan, MSU

Hiroki Osawa, Tokyo Univ.

Jae-Jong Noh

Dipanwita Saha, MU

Nkemdi Anyanwu, MU

Amber Moore, Tuskegee

Joe Adiasor, Mo S&T

Collaborators:

MU

Michael Garcia, Stephen Shannon

Gyeongsang Natl. University/MU

JC Hong, Geon Hui Son

Cornell

Jian Hua

MPIZ Köln

Jane Parker

Katharina Heidrich