We propose a novel Madake (Phyllostachys bambusoides) bamboo suspension culture model for investigation of key enzyme(s) activity involved in growth/differentiation. Sedimented Cell Volume (SCV) and fresh weight (FW) ...We propose a novel Madake (Phyllostachys bambusoides) bamboo suspension culture model for investigation of key enzyme(s) activity involved in growth/differentiation. Sedimented Cell Volume (SCV) and fresh weight (FW) of the suspension cultured cells reached 34% (v/v) and 8.7 g in 10 μM 2,4-dichlorophenoxyacetic acid (2,4-D)-containing medium while only 7% (v/v) SCV and 1.9 g FW of the cells in 10 μM gibberellic acid (GA3)-containing medium in 14 days. Proportion of mitotically active cells (S to G2/M phases) at a log phase was identified as 29.5% in the former cells with tiny cytoplasmic features while 5.4% in the latter cells with elongation, wall thickening, and lignification by using flow cytometry and laser scanning microscopic analysis. The total β-glucosidase (BGL) activity under the 2,4-D condition increased from 4.8 U in day 2 to 26.2 U in day 14 (ca. 5.5-fold) while a slight reduction, from 4.4 U in day 2 to 2.1 U in day 14 (ca. 0.5-fold), occurred when cell division was suppressed under the GA3 condition. Ratio of the BGL activity of the soluble fractions to the membrane-associated fractions varied depending of the culture condition. The ratio was stable (2 to 8) during the culture period under the 2,4-D condition. Interestingly, the activity of the soluble enzyme fractions increased up to ca. 65% under the GA3 condition in inverse proportion to the membrane-associated enzymes. All together, it was strongly suggested that the detected specificity/variability of BGL activity is potentially involved in cell division and lignification in Madake bamboo cells.展开更多
The test site was located in Jincheng Town, Lin’an City, Zhejiang Province. The leaves, culms and rhizomes of two-year-old and three-year-old flowering individuals or nonflowering individuals were taken from the same...The test site was located in Jincheng Town, Lin’an City, Zhejiang Province. The leaves, culms and rhizomes of two-year-old and three-year-old flowering individuals or nonflowering individuals were taken from the same bamboo （Phyllostachys praecox f. prevernalis） forest. The culms and rhizomes of one-year-old flowering or nonflowering were also taken from the same bamboo forest. Based on analysis of the content of endogenous hormones, aminoacid and nutrition in flowering stage of bamboo, the results showed that abscisic acid（ABA） had main effect on accelerating its flowering and the increase of cytokinin（CTK） was also one reason for bringing flower, but indole3acetic acid（IAA）antagonized on its flowering. Total amino-acid in the nonflowering bamboo was 23.01% higher than that in flowering bamboo. Aspartic acid （ASP） could delay flowering. Protein, especially protein in leaves had main effect on senescence procedure. Increase of phosphorus content in flowering bamboo could accelerate metabolizing, and therefore promote senescence of bamboo.展开更多
文摘We propose a novel Madake (Phyllostachys bambusoides) bamboo suspension culture model for investigation of key enzyme(s) activity involved in growth/differentiation. Sedimented Cell Volume (SCV) and fresh weight (FW) of the suspension cultured cells reached 34% (v/v) and 8.7 g in 10 μM 2,4-dichlorophenoxyacetic acid (2,4-D)-containing medium while only 7% (v/v) SCV and 1.9 g FW of the cells in 10 μM gibberellic acid (GA3)-containing medium in 14 days. Proportion of mitotically active cells (S to G2/M phases) at a log phase was identified as 29.5% in the former cells with tiny cytoplasmic features while 5.4% in the latter cells with elongation, wall thickening, and lignification by using flow cytometry and laser scanning microscopic analysis. The total β-glucosidase (BGL) activity under the 2,4-D condition increased from 4.8 U in day 2 to 26.2 U in day 14 (ca. 5.5-fold) while a slight reduction, from 4.4 U in day 2 to 2.1 U in day 14 (ca. 0.5-fold), occurred when cell division was suppressed under the GA3 condition. Ratio of the BGL activity of the soluble fractions to the membrane-associated fractions varied depending of the culture condition. The ratio was stable (2 to 8) during the culture period under the 2,4-D condition. Interestingly, the activity of the soluble enzyme fractions increased up to ca. 65% under the GA3 condition in inverse proportion to the membrane-associated enzymes. All together, it was strongly suggested that the detected specificity/variability of BGL activity is potentially involved in cell division and lignification in Madake bamboo cells.
文摘The test site was located in Jincheng Town, Lin’an City, Zhejiang Province. The leaves, culms and rhizomes of two-year-old and three-year-old flowering individuals or nonflowering individuals were taken from the same bamboo （Phyllostachys praecox f. prevernalis） forest. The culms and rhizomes of one-year-old flowering or nonflowering were also taken from the same bamboo forest. Based on analysis of the content of endogenous hormones, aminoacid and nutrition in flowering stage of bamboo, the results showed that abscisic acid（ABA） had main effect on accelerating its flowering and the increase of cytokinin（CTK） was also one reason for bringing flower, but indole3acetic acid（IAA）antagonized on its flowering. Total amino-acid in the nonflowering bamboo was 23.01% higher than that in flowering bamboo. Aspartic acid （ASP） could delay flowering. Protein, especially protein in leaves had main effect on senescence procedure. Increase of phosphorus content in flowering bamboo could accelerate metabolizing, and therefore promote senescence of bamboo.
基金Supported by the State Forestry Administration of the People’s Republic of China,Project 948(2011-4-49)The Natural Science Foundation of Zhejiang Province(LQ12C16006)The New Variety Breeding of Bamboo of Zhejiang Province(2012C12908-3)
