Welcome! Click here to login or here to register.
Home
Pathways
Proteins
Catalytic RNA molecules
Enzymatic complexes
Structures
Publications
Draw a picture
 
Search
 
Links
Help
Contact





Bujnicki Lab Homepage

"The yeast HAL2 nucleotidase is an in vivo target of salt toxicity."

Murguia JR, Belles JM, Serrano R...



Published 1996-11-15 in J Biol Chem volume 271 .

Pubmed ID: 8910555

The yeast halotolerance gene HAL2 encodes a nucleotidase that dephosphorylates 3'-phosphoadenosine 5'-phosphate (PAP) and 3'-phosphoadenosine 5'-phosphosulfate (PAPS), intermediates of the sulfate assimilation pathway. This nucleotidase is inhibited by Na+ and Li+ but not by K+. Incubation of wild-type yeast cells with NaCl and LiCl, but not with KCl, increased intracellular PAP to millimolar concentrations. No depletion of the pool of adenine nucleotides (AMP, ADP, ATP) was observed. Other stresses such as heat shock or oxidative stress did not result in PAP accumulation. PAPS concentrations also increased during salt stress but remained lower than 0.5 microM. S-Adenosylmethionine concentrations decreased by 50%, reflecting inhibition of sulfate assimilation during salt stress. Salt-induced PAP accumulation was attenuated in a yeast strain overexpressing HAL2. This strain grew better than the wild type under salt stress. These results suggest that the cation sensitivity of the HAL2 nucleotidase is an important determinant of the inhibition of yeast growth by sodium and lithium salts. In addition to blocking sulfate assimilation by product inhibition of PAPS reductase, PAP accumulation may have other unidentified toxic effects.


This publication refers to the following RNApathwaysDB entries:

Pathway

Add your own comment!

There are no comments yet.
Welcome stranger! Click here to login or here to register.