The PmNAC1 gene is induced by auxin and expressed in differentiating vascular cells in callus cultures of Passiflora

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The plant-specific NAM/ATAF/CUC (NAC) transcription factors play critical roles in diverse developmental processes such as the establishment of the shoot apical meristem, lateral root formation, flowering time, senescence, abiotic stress and defense responses. NAC domain transcription factors may be regulated at the transcriptional level by environmental clues, such as hormone concentrations. Here we report the cloning of a Passiflora morifolia putative homolog to a gene encoding a NAC-domain transcription factor, PmNAC1. We have examined the expression patterns of this gene during in vitro callus induction and growth. We observed that the induction of transcript levels of PmNAC1 is correlated to increasing concentrations of 1-naphthalene acetic acid in the culture medium. Additionally, the results of in situ hybridization experiments indicated a dynamic spatial expression pattern for PmNAC1 during callus growth, coincidental with provascular tissue differentiation, especially with xylem cell specification.152275283Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

A Passiflora homolog of a D-type cyclin gene is differentially expressed in response to sucrose, auxin, and cytokinin

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)In higher plants, one of the major components of developmental processes is cell division. The cell division cycle in plants is controlled by cyclins and cyclin-dependend kinases. Nutrient and hormonal signals can influence the roles that D-type cyclins play in the G1-to-S phase transition. Auxins and cytokinins are long known to be important plant hormones controlling plant growth. Additionally, as sucrose is the major transported carbon source in higher plants, it is possible that it plays a major role in cell division. To access the molecular aspects of the effect of auxin, cytokinin and sucrose on the regulation of cell cycle machinery and plant development, we cloned a Passiflora morifolia putative homolog to a D-type cyclin, PmCYCD1, which showed high sequence similarity to other known plant D-type cyclins. We examined the expression patterns of PmCYCD1 during callus induction and growth in in vitro conditions. We observed incremented expression levels of PmCYCD1 correlated to increasing concentrations of sucrose, alpha-naphthalene acetic acid and 6-benzyladenine in the culture medium. Additionally, the results of in situ hybridization experiments indicated a dynamic spatial expression pattern for PmCYCD1 during callus growth.152233242Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

PmTCP1 encodes a putative TCP transcription factor and is differentially expressed during in vitro organogenesis in Passiflora

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The genus Passiflora includes economically important passion fruits and over 600 other wild species. Micropropagation of Passiflora species is far from routine due to low regeneration frequencies and multiplication rates, so there is great interest in understanding the molecular control of the in vitro regeneration processes of these species. Here, we report the characterization of a Passiflora morifolia gene encoding PmTCP1, a putative TCP transcription factor that showed high sequence similarity to Arabidopsis class I TCPs. The expression patterns of the PmTCP1 gene during in vitro organogenesis and callus growth revealed differential expression of PmTCP1 modulated by different combinations of auxin and cytokinin concentrations in the culture medium. At a constant auxin concentration, cytokinin increased PmTCP1 expression, and at a constant cytokinin concentration, auxin repressed PmTCP1 expression. We also observed a correlation between PmTCP1 expression and the in vitro organogenesis of roots and shoots. We expect that these results will increase our understanding of the molecular networks and environmental signals that modulate the processes of organogenesis during plant development.5013644Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq