EgPHI-1, aPHOSPHATE-INDUCED-1gene fromEucalyptus globulus, is involved in shoot growth, xylem fiber length and secondary cell wall properties

Autor(es)

Sousa, Aurizangela O. ^[1] ; Camillo, Luciana R. ^[2] ; Assis, Elza Thaynara C. M. ^[2] ; Lima, Nathalia S. ^[2] ; Silva, Genilson O. ^[2] ; Kirch, Rochele P. ^[3] ; Silva, Delmira C. ^[2] ; Ferraz, Andre ^[4] ; Pasquali, Giancarlo ^[3] ; Costa, Marcio G. C. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Fed Oeste Bahia, Ctr Multidisciplinar, Campus Luis Eduardo Magalhaes, BR-47850000 Luis Eduardo Magalhaes, BA - Brazil

^[2] Univ Estadual Santa Cruz, Dept Ciencias Biol, Ctr Biotecnol & Genet, BR-45662900 Ilheus, BA - Brazil

^[3] Univ Fed Rio Grande do Sul, Ctr Biotecnol, BR-91501970 Porto Alegre, RS - Brazil

^[4] Univ Sao Paulo, Escola Engn Lorena, Dept Biotecnol, BR-12602810 Lorena, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PLANTA; v. 252, n. 3 SEP 2 2020.
• Citações Web of Science: 0

Resumo

Main conclusion EgPHI-1 is a member of PHI-1/EXO/EXL protein family. Its overexpression in tobacco resulted in changes in biomass partitioning, xylem fiber length, secondary cell wall thickening and composition, and lignification. Here, we report the functional characterization of aPHOSPHATE-INDUCED PROTEIN 1homologue showing differential expression in xylem cells fromEucalyptusspecies of contrasting phenotypes for wood quality and growth traits. Our results indicated that this gene is a member of thePHI-1/EXO/EXLfamily. Analysis of the promotercis-acting regulatory elements and expression responses to different treatments revealed that theEucalyptus globulus PHI-1(EgPHI-1) is transcriptionally regulated by auxin, cytokinin, wounding and drought.EgPHI-1overexpression in transgenic tobacco changed the partitioning of biomass, favoring its allocation to shoots in detriment of roots. The stem of the transgenic plants showed longer xylem fibers and reduced cellulose content, while the leaf xylem had enhanced secondary cell wall thickness. UV microspectrophotometry of individual cell wall layers of fibers and vessels has shown that the transgenic plants exhibit differences in the lignification of S2 layer in both cell types. Taken together, the results suggest that EgPHI-1 mediates the elongation of secondary xylem fibers, secondary cell wall thickening and composition, and lignification, making it an attractive target for biotechnological applications in forestry and biofuel crops. (AU)

• Processo FAPESP: 11/50535-2 - Análise micro-espectrofotométrica aplicada ao estudo da recalcitrância em materiais lignocelulósicos
• Beneficiário: Andre Luis Ferraz
• Modalidade de apoio: Auxílio à Pesquisa - Regular