Résumé
Biotic and abiotic stresses are a major factor in decreased production of various cultures around the world. The culture of cacao (Theobroma cacao) has been suffering for many years with one of the diseases that most affect their crops, the witches' broom caused by the fungus Moniliophthora perniciosa. Studies have identified several transcription factors as promising candidates for developed roles in the regulation and signaling via various stresses in plants. bZIP family proteins are transcription factors (TF) that regulate various physiological and development processes, such as seed maturation, vascular development, and responses to biotic and abiotic stresses. Here, we performed an in silico analysis of the bZIP family from Theobroma cacao to subsequently develop a comprehensive phylogenetic analysis in four angiosperms species. For this, bZIP protein sequences of Arabidopsis thaliana were downloaded from the Phytozome database. BLASTP search was performed to identify Solanum lycopersicum, Oryza sativa, Sorghum bicolor and Theobroma cacao bZIP homologs. Analysis of protein domains, search for conserved motifs and alignment of the bZIP proteins were conducted using the PFAM, MEME, CLUSTALW, respectively. The distribution of the bZIP sequences on cacao chromosomes was obtained on the CacaoGenDB site (http://cocoagendb.cirad.fr) using the Interpro number. Protein sequences of the species under study were subjected to a multiple alignment using the software MEGA v5.0, and a Neighbor-joining tree was constructed based on the genetic distance matrix JTT. A classification of the A. thaliana bZIP TFs according to biological function was obtained using the TAIR site (http://www.arabidopsis.org/). We identified 65 bZIPs in cacao, 75 in tomato, 90 in rice and 89 in sorghum. The bZIPs found in cacao were distributed across all 10 chromosomes (Chr), except on chromosome 6, with higher abundance in Chr 01, 02 and 09. According to the study, some region of QTLs related to cacao resistance to witches' broom was located on Chr 2 and 9, may seek markers within genes in this region and use in plant breeding. The bZIP family proteins were grouped into 13 possible orthologous groups based on the classification performed in Arabidopsis thaliana. Five of the cacao bZIP were clustered with proteins highly related to defense to pathogens, being promising candidates for functional study in cacao plants, especially against the witches' broom disease. Funding Agency: FAPESB, CNPq, CAPES and CIRAD. (Texte intégral)