Fundamentals of Viroid Biology

Dr. Charith Raj Adkar-Purushothama PhD has more than 19 years of research experience in molecular biology, bioinformatics, viroid-host interactions, RNA biology and metagenomics. He earned his master’s degree in microbiology from the University of Mysore, India and a doctorate from the University of Milano, Italy. He did his first postdoctoral training with Prof. Teruo Sano at Hirosaki University, Japan, where he worked on the RNA silencing strategies against viroid diseases. He completed his second postdoctoral training in the laboratory of Prof. Jean-Pierre Perreault in the Université de Sherbrooke, Canada, in the field of plant-viroid interaction using biochemistry, molecular biology and bioinformatics tools. He has published over 60 original research articles, four review articles, two book chapters, presented in 30 international scientific conferences, and is a Associate Editor of Fundamental Virology (Frontiers in Virology,) and a Topic Editor for the journal, Viruses. He hold a patent issued by the Government of India. Prof. Teruo Sano PhD is a plant virologist with more than 40 years of research experience in viroid biology, viroid-host interaction, and biotechnology. After obtaining a PhD from Hokkaido University, Japan, he did his postdoctoral studies in Microbiology and Plant Pathology Laboratory, USDA-ARS, Beltsville, the USA, for two years. He joined Hirosaki University as an associate professor in 1992 and became a professor in the year 2005. He received 35 research grants and has published more than 140 original scientific articles, 32 scientific reports, 18 book chapters, and three review articles. He has also holds three patents issued by the Government of Japan. He is an invited speaker for more than 25 scientific meetings. He is one of the virologists who well-balanced both fundamental and applied research. He is one of the pioneering researchers who showed transgenic potato plants expressing a double-strand RNA ribonuclease is resistant to potato spindle tuber viroid. He is a recipient of the 2020 Japan Academy Prize for his studies detecting and isolating viroid's, that causes disease in plants. Prof. Jean-Pierre Perreault completed in BA, MA, and PhD in biochemistry at the University of Montreal, Canada. Under Dr. Robert J. Cedergren, he participated in synthesizing the first mixed RNA/DNA polymers. This pioneering work allowed him to receive the Prix d'Excellence de l'Académie des Grands Montréalais for the biomedical sector's best thesis in 1991. He then completed postdoctoral training at Yale University. Under Professor Sidney Altman's direction, he worked on RNase P's characterization, an enzyme essential for life. Currently, he is the Vice-President, Research and Graduate Studies at the University of Sherbrooke. He was the first director of the RNA Biology Research Center and a co-founder of RiboClub, the Canadian group of researchers interested in studying RNAs. He also chaired the Canadian Society for Biochemistry, Molecular and Cellular Biology. He has more than 25 years of teaching and research experience in Biochemistry, RNA biology, viroid structure and cancer biology. Dr. M. Y. Sreenivasa PhD currently working as Professor and Chairman at Department of Studies in Microbiology, University of Mysore, Manasagangotri, Mysore, India. He is actively involved in research for more than 19 years in the field of mycology, myco-toxicology and Plant pathology. He is also engaged in viroid diseases of the economical plant?in India. He has published more than 100 international/national scientific papers, including 15 book chapters and editorial articles. He is a principal and co-investigator for funded research grants. He has an Indian patent issued by the Govt. of India. In recognition of his research outputs, he was awarded Indo-USA Raman postdoctoral fellowship to visit USA for his post doctoral studies, the International Faculty Development award by the Kennesaw State University, Kennesaw, USA, Indo-Canada Shastri Fellow to visit Ottawa university, Canada. He is an Associate Editor for Frontiers in Microbiology, editing three research topics, member of the review editorial boards of several international journals. He has been invited as Keynote Speakers and Experts in various Plant pathology, microbiology, mycology and Life Sciences-based conferences and workshops. Francesco Di Serio PhD is Research Director at the Consiglio Nazionale delle Ricerche (CNR), Istituto per la Protezione Sostenibile delle Piante (IPSP), SS Bari, Italy. He obtained his PhD degree in Plant Virology at the University of Naples Federico II. His PhD and early postdoctoral research focused on viroids' characterization in the laboratory directed by Prof. Ricardo Flores (CSIC-Universidad Politécnica de Valencia, Spain). His second postdoc was carried out in the laboratory directed by Prof. Frederick Meins (Friedrich Miescher Institute, Basel, Switzerland), where he studied RNA silencing and virus movement in tobacco. Currently, Dr.. Di Serio is a Member and Vice-Chair of the Plant Health Panel of the European Food Safety Authority (EFSA). He is Member of Accademico aggregato) of the Georgofili Accademy. Since 2011, he has chaired the Viroid Study Group of the International Committee on Taxonomy of Viruses. In 2014, F. Di Serio obtained the Italian National Scientific Habilitation as a full professor in Plant Pathology and Entomology. He has more than 25 years of teaching and research experience in viroid characterization, taxonomy, characterization of novel viroid-like RNAs and viruses and has published in a hundred research articles in refereed journals. José-Antonio Daròs PhD is a Research Professor at the Institute for Plant Molecular and Cell Biology (IBMCP) where he supervises the research group "Plant Virus Biotechnology." Dr. Daròs obtained his degree in Biological Sciences at the University of Valencia (Spain) and his PhD in this same University, with research work about viroid replication. He gained postdoctoral experience working in potyvirus molecular biology for three years and a half in the laboratory of Prof. James C. Carrington at Texas A&M University and Washington State University in the USA. He joined the laboratory of Prof. Ricardo Flores at IBMCP in 1998, investigating the viroid-plant interaction. In 2004, he obtained his own CSIC permanent position as a Scientist in this same Institute. Dr. Daròs has more than 25 years of teaching and research experience and authored more than one hundred research, review articles and book chapters about various aspects of plant virus, viroid biology, and biotechnology.

Preface

Dedication

Opening words

Introductory Statement

Section 1 Introduction

1. Milestones in viroid research

2. Viroid taxonomy

3. Structure of viroids

4. Replication and movement of viroids in host plants

Section 2 Prospecting for viroid

5. Viroids diseases and its distribution in Asia

6. Viroid associated plant diseases in Europe

7. Naturally occurring viroid diseases of economically important plants in Africa

8. Naturally occurring viroids and viroid-related sequences in the tropical monocotyledons of Oceania

9. Viroids diseases and its distribution in North America

10. Viroid associated plant diseases in South America

Section 3 Viroid pathogenesis and viroid-host interaction

11. Viroid pathogenicity

12. Viroid and protein translation

13. Effect of viroid on host DNA methylation pathways

14. Transcriptomic analyses provide insights into plant-viroid interactions

15. Viroid-induced RNA silencing and its secondary effect on the host transcriptome Section 4 Viroid disease management

16. Detection of viroids

17. Viroid Disease Control and Strategies

18. Policies, regulations and viroid free clean plant material for sustainable agriculture Section 5 Prospective

19. Application of bioinformatics in viroid research

20. Viroid-derived methods for puri?cation, diagnostics, and secondary structure prediction

21. Future perspectives in viroid research