Stress response of plant H+-PPase-expressing transgenic Escherichia coli and Saccharomyces cerevisiae: a potentially useful mechanism for the development of stress-tolerant organisms.
The simple proton-translocating inorganic pyrophosphatase (H(+)-PPase) found in plants and protists is an evolutionally conserved, essential enzyme that catalyzes the hydrolysis of pyrophosphate (PPi). Little is known about the functional contribution of H(+)-PPase to the cellular response to abiotic stresses, except its high salinity and drought stress. To investigate the role of H(+)-PPase during response to cellular stress, we isolated the cDNA of Arabidopsis thaliana H(+)-PPase (AVP1) and Oryza sativa H(+)-PPase (OVP1) and constructed transgenic Saccharomyces cerevisiae and Escherichia coli lines that express AVP1 and OVP1. In S. cerevisiae, the expression of a chimeric derivative of the AVP1 and OVP1 alleviated the phenotype associated with ipp2-deficient cells in the presence of high salinity (NaCl) and metal stressors (Cd, Mn, and Zn). In E. coli, AVP1 and OVP1 overexpression conferred enhanced tolerance to abiotic stresses, including heat shock and H(2)O(2), as well as NaCl, Cd, Mn, Zn, Ca, and Al. Interestingly, AVP1 and OVP1 overexpression resulted in hypersensitivity to menadione and cobalt. These results demonstrate the cellular capacity of AVP1- and OVP1-expressing transgenic yeast and E. coli in response to physiological, abiotic stresses. Moreover, our results suggest new ways of engineering stress-tolerant plants that are capable of responding to climate change. Here, we provide an outline of an experimental system to examine the alternative roles of plant H(+)-PPase.
Advanced Bio-resource Research Center, Kyungpook National University, #1370 Sankyuk-dong, Buk-gu, Daegu, 702-701, Republic of Korea.
Ho-Sung
HS
Yoon
Saeng-Young
SY
Kim
Il-Sup
IS
Kim
D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics; D011756:Diphosphates / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D018014:Gene Transfer Techniques; D043564:Inorganic Pyrophosphatase / Q000235:genetics* / Q000378:metabolism; D012275:Oryza / Q000201:enzymology / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D013312:Stress, Physiological / Q000235:genetics
D029681:Arabidopsis Proteins; D011756:Diphosphates; C107241:diphosphoric acid; C505048:AVP1 protein, Arabidopsis; D043564:Inorganic Pyrophosphatase