Identification of novel membrane transporters associated with potassium acquisition and homeostasis
Year: 2004
Type: dissertation
Abstract: Potassium has long been associated with many different cellular processes such as enzyme activation and osmoregulation. Because of its important role in cellular metabolism, K+ is maintained at high and stable concentrations in the cytoplasm in relation to varying K+ external conditions. This is achieved through synergistic low- and high-affinity mechanisms, which incorporate different ion channels/carriers and pumps located across different membranes within and across different tissues. As potassium homeostasis is a complex process, analysis at the single-gene level would make it virtually impossible to obtain a complete view of membrane transporter processes. This is why a microarray approach was adopted, in order to obtain a broader picture of K+ regulatory pathways. Whilst full genome chips are effective at gaining global expression profiles, we have narrowed the field to exclusively look at Arabidopsis Membrane Transporters through a customised AMT chip that contains probes for 1250 known and putative transporters. Expression changes of membrane transporters were investigated in response to abiotic stress, mimicked by addition of ABA to 2-week-old A.thaliana seedlings grown in potassium-rich or potassium-deplete conditions. Our preliminary results indicate that at least three types of transporters showed consistent but different expression patterns. These included members of the MATE family, a novel putative transporter with 7 predicted transmembrane spanning domains (7TMS) as well as the high-affinity transporter HAK5.
Author: Caroline Blake
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: green
OpenAlex ID: W2972042413