Gtpases: Versatile Regulators of Signal Transduction in Plants

ISBN-13: 9783319116105 / Angielski / Miękka / 2014 / 81 str.

Girdhar K. Pandey; Manisha Sharma; Amita Pandey

Opis

G proteins are the key regulators for a wide range of cellular processes in animals and plants. In comparison to animals and yeast, plants have a single Rho-GTPase subfamily called Rho-like GTPases (ROPs). The ROP family of monomeric GTPases has emerged as a versatile and key regulator in plant signal transduction processes. During the past few years' studies on plant RHO-type (ROP) GTPase have generated new insights into their role in diverse processes ranging from cytoskeletal organization, polar growth, development to stress and hormonal responses. Studies have shown that plants have evolved specific regulators and effector molecules. ROP GTPases possess the ability to interact with these multiple regulator and effector molecules that ultimately determines their signaling specificity. Recently, genome wide studies in plants have shown that the Arabidopsis genome encodes 93, and rice has nearly 85 small GTPase homologs. And we have been able to identify four new homologs in the rice genome. Here, we focus on the complete phylogenetic, domain, structural and expression analysis during stress and various developmental processes of small GTPases in plants. The comparison of gene expression patterns of the individual members of the GTPase family may help to reveal potential plant specific signaling mechanisms and their relevance. Also, we are summarizing the role of currently known ROP GTPases and their interacting proteins with brief description, simultaneously, comparing their expression pattern based on microarray data. Overall, we will be discussing the functional genomic perspective of plant Rho like GTPases and their role in regulating several physiological processes such as stress, hormonal, pollen tube, root hair-growth and other developmental responses.​

Spis treści

1.      Overview of G proteins (GTP binding proteins) in Eukaryotes

1.1 Overview

1.2 Small G-protein structure and Domain features

1.3 Biochemical regulation of small GTPases

1.4 GEFs

1.5 GAPs

1.6 GDIs

1.7 Localization and Post-translational modifications      

References  

2.      Overview of Small GTPase Signaling Proteins in Plants

2.1  Abstract

2.2  Introduction

2.3  Small GTPase Complement in Plantae

2.4  Plant Specific Functions of ROPs

References

 

3.      Identification and Classification of Rho GTPases in Plants

3.1  Introduction

3.2  Nomenclature

3.3  ROP GTPase complement in Arabidopsis

3.4  ROP GTPase complement in rice

References

 

4.      Sequence, Structure, and Domain Analysis of GTPases in Plants

 

4.1  Introduction

4.2  Domain Identification and Confirmation of Rice Small GTPases

4.3  Multiple alignment and phylogenetic analysis

4.4  Comparative Phyletic analysis of Rice Small GTPase genes

4.5  Gene nomenclature and localization of small GTPases

4.6  G-Domain Conservation Pattern

References

 

5.      Expression of Small GTPases Under Stress and Developmental Conditions in Plants

 

5.1  Expression Pattern of OsGTPases in Abiotic Stress

5.2  Expression Pattern of OsGTPases in Developmental Stages

5.3  Expression Pattern of OsGTPases during Phytohormone treatment

5.4  Expression Pattern of AtGTPases in Devlopmental stages

5.5  Expression Pattern of AtGTPases in Abiotic Stress  

5.6  Expression Pattern of AtGTPases during Phytohormone treatment

References

 

6.      Emerging Roles of Rho GTPases in Plants

 

6.1     Rho GTPases: Versatile signaling molecules in plants

6.2     Rho Activates plant defense mechanisms

6.3     Role in intracellular trafficking and cell polarity

6.4     Role in pollen tube growth

6.5     Role in root hair development

6.6     Small GTPases Controls Cell Morphogenesis

References

 

7.      Cellular Localization of Small GTPases

 

7.1  Membrane association of RAC/ROP GTPase

7.2     Hypervariable Region regulate RAC/ROP localization

7.3     Post-translational Lipid Modifications determines the ROP Activity

7.4     Significance of Subcellular localization in ROP Signaling

References

 

8.      Functional Genomic Perspective of Small GTPases

 

8.1  Regulatory mechanism of Rho signaling

8.1.1        Regulators and Effectors of ROP

8.1.2        ROP interactive CRIB domain containing proteins (RICs)

8.1.3        Two counteractive pathways coordinate the actin dynamics in pollen tube elongation

8.1.4        The antagonistic ROP2/RIC1 pathway promote microtubule organization

 

8.2  Unconventional effectors of ROP/RAC pathways

References

9.      Systemic Approaches to Resolve Spatio-Temporal Regulation of GTPase Signaling

 

9.1  Introduction

9.2  Detection of Rho GTPase activity in plant cells

9.3  FRET (fluorescence resonance energy transfer) assay

9.4  Biochemical assay for ROP activity detection

9.5  Light-gated protein interaction

9.6 Significance of Systemic Approaches to Measure Signaling Modularity

References

 

10.  Key Questions and Future Prospects

 

10.1          Introduction

10.2          GTPase and lipid interaction

10.3          Upstream and downstream regulators

10.4          Future perspectives

References

 

 

 

 

 

O autorze

Girdhar K. Pandey

Department of Plant Molecular Biology

Delhi University South Campus

Dhaula Kuan, New Delhi

India

 Manisha Sharma

Department of Plant Molecular Biology

Delhi University South Campus

Dhaula Kuan, New Delhi

India

 Amita Pandey

Department of Plant Molecular Biology

Delhi University South Campus

Dhaula Kuan, New Delhi

India

 Thiruvekadam Shanmugam

Division of Biosciences and Bioinformatics

Myongji University

Kyunggi-do

Republic of South Korea