Genetics and Molecular Biology (Jan 2007)

CitEST libraries

  • Maria Luísa P. Natividade Targon,
  • Marco Aurélio Takita,
  • Alexandre M. do Amaral,
  • Alessandra A. de Souza,
  • Eliane Cristina Locali-Fabris,
  • Sílvia de Oliveira Dorta,
  • Kleber Martins Borges,
  • Juliana Mendonça de Souza,
  • Carolina Munari Rodrigues,
  • Adriano Reis Lucheta,
  • Juliana Freitas-Astúa,
  • Marcos Antonio Machado

DOI
https://doi.org/10.1590/S1415-47572007000500030
Journal volume & issue
Vol. 30, no. 3
pp. 1019 – 1023

Abstract

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In order to obtain a better understanding of what is citrus, 33 cDNA libraries were constructed from different citrus species and genera. Total RNA was extracted from fruits, leaves, flowers, bark, seeds and roots, and subjected or not to different biotic and abiotic stresses (pathogens and drought) and at several developmental stages. To identify putative promoter sequences, as well as molecular markers that could be useful for breeding programs, one shotgun library was prepared from sweet orange (Citrus sinensis var. Olimpia). In addition, EST libraries were also constructed for a citrus pathogen, the oomycete Phythophthora parasitica in either virulent or avirulent form. A total of 286,559 cDNA clones from citrus were sequenced from their 5’ end, generating 242,790 valid reads of citrus. A total of 9,504 sequences were produced in the shotgun library and the valid reads were assembled using CAP3. In this procedure, we obtained 1,131 contigs and 4,083 singletons. A total of 19,200 cDNA clones from P. parasitica were sequenced, resulting in 16,400 valid reads. The number of ESTs generated in this project is, to our knowledge, the largest citrus sequence database in the world.

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