Article

Isolation and characterization of P-type H(+)-ATPase genes from potato.

Institut für Genbiologische Forschung, Berlin, FRG.
Plant Molecular Biology (Impact Factor: 4.07). 12/1994; 26(3):979-88. DOI: 10.1007/BF00028864
Source: PubMed

ABSTRACT H(+)-ATPase cDNAs were identified in a potato leaf library using an Arabidopsis gene as a probe. Based on their sequences, the clones could be grouped into at least two classes. A similar classification was obtained from the analysis of sequence data from four tobacco genes. Both potato genes are expressed in all tissues analysed, higher levels of expression were found in leaves and stem than in roots and tubers. For both genes, no significant differences in level of expression could be detected under a variety of conditions such as cold treatment, anaerobiosis, sucrose induction or treatment with a synthetic cytokinin. Only 2,4-D and prolonged periods of darkness lead to a slight reduction in mRNA levels. The reduction in darkness was compensated after transfer of the plants back into the light. Expression of the ATPase genes remained constant in transgenic plants which are inhibited in phloem loading due to antisense inhibition of the sucrose transporter. On the other hand, expression of the sucrose transporter is inducible by auxin and cytokinin but not by sucrose. Taken together, these data suggest that at least the two plasma membrane H(+)-ATPase genes analysed are rather constant in their expression and that either other genes respond to external stimuli or that most of the regulation occurs at the posttranscriptional level.

1 Bookmark
 · 
81 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Leaf sheaths of higher position leaves (upper leaf sheaths) on rice (Oryza sativa L.) stems function as temporary starch storage organs at the pre-heading stage. Starch is quickly accumulated in upper leaf sheaths before heading, but the storage starch is degraded at the post-heading stage to provide the carbon source for developing grains. Abscisic acid (ABA) is a key plant hormone to control plant development and stress responses. This study found that ABA content in upper leaf sheaths was significantly increased at the stage after panicle exsertion and that the pattern of ABA increase was negatively correlated with changes in starch content. Exogenous ABA reduced starch content in leaf sheaths while the activities of starch degradation enzymes (i.e., α-amylase/EC 3.2.1.1, β-amylase/EC 3.2.1.2) increased in ABA-treated leaf sheaths and sucrose transporter gene expression was up-regulated. However, ABA repressed the activities of some starch biosynthesis enzymes (i.e., ADP-glucose pyrophosphorylase/EC 2.7.7.27, granule-bound starch synthase/EC 2.4.1.11) in leaf sheaths. These results suggest that ABA plays an important role in promoting starch degradation and sucrose remobilization in upper leaf sheaths at the post-heading stage.
    Acta Physiologiae Plantarum 07/2012; 34(4). · 1.52 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The role of plasma membrane-localized sucrose transporter (NtSUT1) was investigated using cultured tobacco cell (Nicotiana tabacum L.) line BY-2. The wild type (WT) cells were first transformed with the NtSUT1 gene or its fragments cloned from tobacco cell line SL to form the over-expression (OX) and suppression (RNAi) cell lines, respectively. Using OX and RNAi transgenics, the role of NtSUT1 in growth capacity of actively growing cells and in aluminum (Al)-treated cells was examined. During the logarithmic phase of growth in nutrient medium containing 2,4-dichlorophenoxyacetic acid (2,4-D), both the rate of sucrose uptake measured with radio-tracer and the content of soluble sugars were higher in OX and lower in RNAi cell lines compared to WT. Overall, the content of soluble sugars negatively correlated with the time necessary for doubling mass (fresh weight). When cells were treated without (control) or with Al in a simple medium containing calcium, sucrose and 2-(N-morpholino)ethanesulfonic acid (MES; pH 5.0) for up to 18 h, the expression of NtSUT1 under its native promoter, or under the control of strong constitutive cauliflower mosaic virus (CaMV) 35S promoter, was strongly dependent on the presence of 2,4-D. Thereafter, the cells were preferentially treated in the presence of 2,4-D. During 6 h after a start of the control treatment, sucrose uptake rates were, compared to WT, slightly higher and lower in OX and RNAi lines respectively. The addition of Al reduced the sucrose uptake rates of OX and WT to the level of RNAi line, indicating that Al inhibits sucrose uptake via NtSUT1. During the post-Al culture of control and Al-treated cells in a nutrient medium, sucrose uptake rates were much higher in OX compared to WT and RNAi lines, which closely and positively correlated with the growth capacity of the cells. Judging from the growth capacity of Al-treated cells relative to that of control cells, OX cells were more tolerant to Al than WT and RNAi. In summary, we conclude that over-expression of NtSUT1 confers higher growth capacity in actively growing cells as well as in Al-treated cells.
    Soil Science and Plant Nutrition 12/2013; 59(5):756-770. · 0.75 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Westag 97 has larger capacity of Cd accumulation in roots which prevents Cd from translocating into stems and leaves; conversely, AC Hime has smaller capacity of Cd accumulation in roots; more Cd is transported into stems and leaves. The different capacity of Cd in roots between Westag 97 and AC Hime causes the different Cd concentration in seeds. Meanwhile, according to the different expression levels of RSTK, ISCP, and H(+)-ATPase between Westag 97 and AC Hime, RSTK may be involved in transporting Cd into stems and leaves; H(+)-ATPase may be correlated to the capacity of Cd accumulation in roots; and Cd caused some changes of fundamental life process which leaded to the different expression patterns of ISCP between Westag 97 and AC Hime.
    TheScientificWorldJournal. 01/2014; 2014:979750.

Full-text

Download
50 Downloads
Available from
May 27, 2014