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

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.

A New Subfamily of Sucrose Transporters, SUT4, with Low Affinity/High Capacity Localized in Enucleate Sieve Elements of Plants

“…The increase in sucrose transport activity caused by modification of a conserved histidine in the first external loop (Lu and Bush, 1998) indicates that sucrose transporters may be directly regulated at the protein level. In addition, the amounts of mRNA for sucrose transporter SUT1 from potato are developmentally controlled and hormonally regulated (Riesmeier et al, 1993;Harms et al, 1994).…”

“…The increase in sucrose transport activity caused by modification of a conserved histidine in the first external loop (Lu and Bush, 1998) indicates that sucrose transporters may be directly regulated at the protein level. In addition, the amounts of mRNA for sucrose transporter SUT1 from potato are developmentally controlled and hormonally regulated (Riesmeier et al, 1993;Harms et al, 1994).Clearly, multiple kinetic components of sucrose uptake are present in leaves (Delrot and Bonnemain, 1981;Maynard and Lucas, 1982). As demonstrated by autoradiography, 14 C-sucrose, externally applied to source leaves of Vicia faba or Beta vulgaris , is taken up by mesophyll cells and phloem (Fondy and Geiger, 1977;Giaquinta, 1977;Delrot, 1981).…”

Plant Plasma Membrane H+-ATPase in Adaptation of Plants to Abiotic Stresses

“…It has been shown that various genes are expressed in the same organ. Moreover, even within the same cell type at the same developmental stage, at least two H + -ATPase genes are expressed (Harms et al, 1994;Hentzen et al, 1996;Moriau et al, 1999). In N. plumbaginifolia two different plasma membrane H + -ATPase genes, PMA2 and PMA4, are expressed in guard cells (Moriau et al, 1999).…”

“…With such a phenomenon the amount of H + -ATPase might be increased under conditions requiring greater transport activity. The external signals result in changes in plant plasma membrane H + -ATPase gene expression, include salt (Niu et al, 1993;Binzel, 1995;JanickaRussak & Kłobus, 2007), low temperature (Ahn et al, 1999(Ahn et al, , 2000, heavy metals (JanickaRussak et al, 2008), dehydration (Surowy et al, 1991), light conditions (Harms et al, 1994), mechanical stress (Oufattole et al, 2000) and externally applied hormones (Frías et al, 1996).…”

Sugar Regulates mRNA Abundance of H+-ATPase Gene Family Members in Tomato

“…Multiple genes encoding PM H+-ATPases have been cloned in tomato (Lycopersicon esculentum; Ewing et al, 1990;Ewing and Bennett, 1994), Nicotiana plumbaginifolia (Boutry et al, 1989;Perez et al, 1992;Moriau et al, 1993), Arabidopsis fhaliana (Harper et al, , 1990(Harper et al, , 1994Pardo and Serrano, 1989;Houlne and Boutry, 1994), potato (Harms et al, 1994), rice (Wada et al, 1992;Ookura et al, 1994), and Vicia faba (L.E. Wimmers, unpublished data).…”