The Mutador system in sugarcane: a comparative analysis with rice

Author(s)

Nilo Luiz Saccaro Junior

• Document type: Master's Dissertation
• Press: São Paulo. , ilustrações, tabelas.
• Institution: Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB)
• Defense date: 2007-11-27

Examining board members

Maria Magdalena Rossi; Mariana Cabral de Oliveira; Maria Lucia Carneiro Vieira

• Advisor: Maria Magdalena Rossi
• Field of knowledge: Biological Sciences - Genetics
• Indexed in: Banco de Dados Bibliográficos da USP-DEDALUS; Biblioteca Digital de Teses e Dissertações - USP
• Location: Universidade de São Paulo. Biblioteca do Instituto de Biociências; M-1317

Abstract

Transposable elements (TEs) constitute great part of eukaryote genetic material, in grasses, they comprise between 50-80% of the genome. Genome projects have significantly increased the amount of information about these elements, revealing their importance and allowing the development of new approaches for their study. The Mutator system (Mu) of maize is the most active and mutagenic plant transposon. Beyond the autonomous element, MuDR, the system comprises a very heterogeneous, in sequence and structure, set of elements, called MuLEs, that can contain even host gene fragments. The most abundant transposon related sequences expressed in sugarcane transcriptoma are the MuDR-like. They group into four clades (called Classes I, II, III and IV) that exist prior to the Mono and Eudicot split. The aim of this work is to gain knowledge about the Mutator system in sugarcane through the comparative analysis against rice (whose genome is completely sequenced). The results described the abundance and diversity of the Mu system in grasses, evidencing a clado-specific amplification with a burst of Class II along the evolution of this plant group. Structural analyses showed that, while Classes I and II comprise elements with transposon characteristics, Classes III and IV are domesticated transposases. One BAC clone from each sugarcane parental genotype (Saccharum officinarum and Saccharum spontaneum) have been completely sequenced, both containing Class III elements. These elements have been characterized and the sugarcane genomic sequences were compared with their orthologues in rice. The comparative analyses showed an accumulation of TEs in the intergenic regions. (AU)

• FAPESP's process: 07/54162-0 - The Mutator system in sugarcane: a comparative analysis with rice
• Grantee: Nilo Luiz Saccaro Junior
• Support Opportunities: Scholarships in Brazil - Master