Maize bushy stunt phytoplasma SMP11 effector protein: interaction with Arabidopsis and Maize transcription factors and genomic comparison among isolates

• Grant number: 13/26982-4
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Effective date (Start): April 01, 2014
• Effective date (End): December 31, 2014
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Joao Roberto Spotti Lopes
• Grantee: Maria Cristina Canale Rappussi da Silva
• Supervisor: Saskia A. Hogenhout
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Research place: John Innes Centre, England
• Associated to the scholarship: 12/51867-1 - Maize bushy stunt phytoplasma SMP11 effector protein: genetic comparison between isolates and role in maize bushy stunt phytoplasma symptomatology, BP.PD

Abstract

Maize bushy stunt phytoplasma (MBSP) is a vector-borne phloem-limited bacteria transmitted by the corn leafhopper, Dalbulus maidis, and is associated with an important corn stunting disease in Brazil, characterized by leaf reddening, shortening of internodes, plant height reduction, lower grain yield and, occasionally, lateral shoot production. It has been recently shown that phytoplasmas have effector proteins that interfere with plant development and aid disease spread in nature by affecting plant defenses against vectors. Aster Yellows strain Witches' Broom phytoplasma secretes the effector protein SAP11, which destabilizes TCP transcription factors that control plant development in Arabidopsis thaliana leading to lateral shoot branching and leaf crinkling and also down regulation of genes involved in the synthesis of jasmonate, allowing the leafhopper vector Macrosteles quadrilineatus to produce more offspring on infected plants. A gene that codes for a homologous effector protein (secreted MBSP protein 11 - SMP11) was identified in a Mexican isolate of MBSP. It is hypothesized that SMP11 of Brazilian populations of MBSP may interact and destabilize TCPs involved in maize plant development, inducing typical MBS disease symptoms, such as witches' brooms (bushy-looking maize plants), and higher reproduction rates of the MBSP vector. During internship at the John Innes Centre (JIC) in the UK, the postdoctoral researcher will conduct studies on SMP11 effector protein interactions with plant TCPs using yeast two-hybrid and in planta co-infiltration analyses. Jasmonate production will be assessed on SMP11 transgenic Arabidopsis, and the survival and fecundity of leafhoppers on those plants. Additionally, identification and comparative analyses of candidate effectors in the sequenced genomes of Brazilian MBSP isolates will be carried out. The obtained results will help in the understanding of phytoplasma-host plant interactions, with possible applications on breeding programs for maize resistance to the pathogen. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CHANG, HSING-HUA; CHO, SHU-TING; CANALE, MARIA C.; MUGFORD, SAM T.; LOPES, JOAO R. S.; HOGENHOUT, SASKIA A.; KUO, CHIH-HORNG. Complete Genome Sequence of ``Candidatus Sulcia muelleri{''} ML, an Obligate Nutritional Symbiont of Maize Leafhopper (Dalbulus maidis). MICROBIOLOGY RESOURCE ANNOUNCEMENTS, v. 3, n. 1, JAN-FEB 2015. (13/26982-4, 12/50217-3)

CHANG, HSING-HUA; CHO, SHU-TING; CANALE, MARIA C.; MUGFORD, SAM T.; LOPES, JOAO R. S.; HOGENHOUT, SASKIA A.; KUO, CHIH-HORNG. Complete Genome Sequence of "Candidatus Sulcia muelleri" ML, an Obligate Nutritional Symbiont of Maize Leafhopper (Dalbulus maidis). GENOME ANNOUNCEMENTS, v. 3, n. 1, p. 2-pg., 2015-01-01. (13/26982-4, 12/50217-3)